diff --git a/msrplib/protocol.py b/msrplib/protocol.py
index 46c901f..f6d2038 100644
--- a/msrplib/protocol.py
+++ b/msrplib/protocol.py
@@ -1,753 +1,753 @@
 # Copyright (C) 2008-2012 AG Projects. See LICENSE for details
 
 import random
 import re
 
 from collections import deque, namedtuple
 from application.system import host as host_module
 from twisted.internet.protocol import connectionDone
 from twisted.protocols.basic import LineReceiver
 
 from msrplib import MSRPError
 
 
 class ParsingError(MSRPError):
     pass
 
 
 class HeaderParsingError(ParsingError):
     def __init__(self, header, reason):
         self.header = header
         ParsingError.__init__(self, 'Error parsing {} header: {}'.format(header, reason))
 
 
 # Header value data types (for decoded values)
 #
 
 ByteRange = namedtuple('ByteRange', ['start', 'end', 'total'])
 Status = namedtuple('Status', ['code', 'comment'])
 ContentDisposition = namedtuple('ContentDisposition', ['disposition', 'parameters'])
 
 
 # Header value types (describe how to encode/decode the value)
 #
 
 class SimpleHeaderType(object):
     data_type = object
 
     @staticmethod
     def decode(encoded):
         return encoded
 
     @staticmethod
     def encode(decoded):
         return decoded
 
 
 class UTF8HeaderType(object):
     data_type = unicode
 
     @staticmethod
     def decode(encoded):
         return encoded.decode('utf-8')
 
     @staticmethod
     def encode(decoded):
         return decoded.encode('utf-8')
 
 
 class URIHeaderType(object):
     data_type = deque
 
     @staticmethod
     def decode(encoded):
         return deque(parse_uri(uri) for uri in encoded.split(' '))
 
     @staticmethod
     def encode(decoded):
         return ' '.join(str(uri) for uri in decoded)
 
 
 class IntegerHeaderType(object):
     data_type = int
 
     @staticmethod
     def decode(encoded):
         return int(encoded)
 
     @staticmethod
     def encode(decoded):
         return str(decoded)
 
 
 class LimitedChoiceHeaderType(SimpleHeaderType):
     allowed_values = frozenset()
 
     @classmethod
     def decode(cls, encoded):
         if encoded not in cls.allowed_values:
             raise ValueError('Invalid value: {!r}'.format(encoded))
         return encoded
 
 
 class SuccessReportHeaderType(LimitedChoiceHeaderType):
     allowed_values = frozenset({'yes', 'no'})
 
 
 class FailureReportHeaderType(LimitedChoiceHeaderType):
     allowed_values = frozenset({'yes', 'no', 'partial'})
 
 
 class ByteRangeHeaderType(object):
     data_type = ByteRange
 
     regex = re.compile(r'(?P<start>\d+)-(?P<end>\*|\d+)/(?P<total>\*|\d+)')
 
     @classmethod
     def decode(cls, encoded):
         match = cls.regex.match(encoded)
         if match is None:
             raise ValueError('Invalid byte range value: {!r}'.format(encoded))
         start, end, total = match.groups()
         start = int(start)
         end = int(end) if end != '*' else None
         total = int(total) if total != '*' else None
         return ByteRange(start, end, total)
 
     @staticmethod
     def encode(decoded):
         start, end, total = decoded
         return '{}-{}/{}'.format(start, end or '*', total or '*')
 
 
 class StatusHeaderType(object):
     data_type = Status
 
     @staticmethod
     def decode(encoded):
         namespace, sep, rest = encoded.partition(' ')
         if namespace != '000' or sep != ' ':
             raise ValueError('Invalid status value: {!r}'.format(encoded))
         code, _, comment = rest.partition(' ')
         if not code.isdigit() or len(code) != 3:
             raise ValueError('Invalid status code: {!r}'.format(code))
         return Status(int(code), comment or None)
 
     @staticmethod
     def encode(decoded):
         code, comment = decoded
         if comment is None:
             return '000 {:03d}'.format(code)
         else:
             return '000 {:03d} {}'.format(code, comment)
 
 
 class ContentDispositionHeaderType(object):
     data_type = ContentDisposition
 
     regex = re.compile(r'(\w+)=("[^"]+"|[^";]+)')
 
     @classmethod
     def decode(cls, encoded):
         disposition, _, parameters = encoded.partition(';')
         if not disposition:
             raise ValueError('Invalid content disposition: {!r}'.format(encoded))
         return ContentDisposition(disposition, {name: value.strip('"') for name, value in cls.regex.findall(parameters)})
 
     @staticmethod
     def encode(decoded):
         disposition, parameters = decoded
         return '; '.join([disposition] + ['{}="{}"'.format(name, value) for name, value in parameters.iteritems()])
 
 
 class ParameterListHeaderType(object):
     data_type = dict
 
     regex = re.compile(r'(\w+)=("[^"]+"|[^",]+)')
 
     @classmethod
     def decode(cls, encoded):
         return {name: value.strip('"') for name, value in cls.regex.findall(encoded)}
 
     @staticmethod
     def encode(decoded):
         return ', '.join('{}="{}"'.format(name, value) for name, value in decoded.iteritems())
 
 
 class DigestHeaderType(ParameterListHeaderType):
     @classmethod
     def decode(cls, encoded):
         algorithm, sep, parameters = encoded.partition(' ')
         if algorithm != 'Digest' or sep != ' ':
             raise ValueError('Invalid Digest header value')
         return super(DigestHeaderType, cls).decode(parameters)
 
     @staticmethod
     def encode(decoded):
         return 'Digest ' + super(DigestHeaderType, DigestHeaderType).encode(decoded)
 
 
 # Header classes
 #
 
 class MSRPHeaderMeta(type):
     __classmap__ = {}
 
     name = None
 
     def __init__(cls, name, bases, dictionary):
         type.__init__(cls, name, bases, dictionary)
         if cls.name is not None:
             cls.__classmap__[cls.name] = cls
 
     def __call__(cls, *args, **kw):
         if cls.name is not None:
             return super(MSRPHeaderMeta, cls).__call__(*args, **kw)  # specialized class, instantiated directly.
         else:
             return cls._instantiate_specialized_class(*args, **kw)   # non-specialized class, instantiated as a more specialized class if available.
 
     def _instantiate_specialized_class(cls, name, value):
         if name in cls.__classmap__:
             return super(MSRPHeaderMeta, cls.__classmap__[name]).__call__(value)
         else:
             return super(MSRPHeaderMeta, cls).__call__(name, value)
 
 
 class MSRPHeader(object):
     __metaclass__ = MSRPHeaderMeta
 
     name = None
     type = SimpleHeaderType
 
     def __init__(self, name, value):
         self.name = name
         if isinstance(value, str):
             self.encoded = value
         else:
             self.decoded = value
 
     def __eq__(self, other):
         if isinstance(other, MSRPHeader):
             return self.name == other.name and self.decoded == other.decoded
         return NotImplemented
 
     def __ne__(self, other):
         return not self == other
 
     @property
     def encoded(self):
         if self._encoded is None:
             self._encoded = self.type.encode(self._decoded)
         return self._encoded
 
     @encoded.setter
     def encoded(self, encoded):
         self._encoded = encoded
         self._decoded = None
 
     @property
     def decoded(self):
         if self._decoded is None:
             try:
                 self._decoded = self.type.decode(self._encoded)
             except Exception as e:
                 raise HeaderParsingError(self.name, str(e))
         return self._decoded
 
     @decoded.setter
     def decoded(self, decoded):
         if not isinstance(decoded, self.type.data_type):
             try:
                 # noinspection PyArgumentList
                 decoded = self.type.data_type(decoded)
             except Exception:
                 raise TypeError('value must be an instance of {}'.format(self.type.data_type.__name__))
         self._decoded = decoded
         self._encoded = None
 
 
 class MSRPNamedHeader(MSRPHeader):
     def __init__(self, value):
         MSRPHeader.__init__(self, self.name, value)
 
 
 class ToPathHeader(MSRPNamedHeader):
     name = 'To-Path'
     type = URIHeaderType
 
 
 class FromPathHeader(MSRPNamedHeader):
     name = 'From-Path'
     type = URIHeaderType
 
 
 class MessageIDHeader(MSRPNamedHeader):
     name = 'Message-ID'
     type = SimpleHeaderType
 
 
 class SuccessReportHeader(MSRPNamedHeader):
     name = 'Success-Report'
     type = SuccessReportHeaderType
 
 
 class FailureReportHeader(MSRPNamedHeader):
     name = 'Failure-Report'
     type = FailureReportHeaderType
 
 
 class ByteRangeHeader(MSRPNamedHeader):
     name = 'Byte-Range'
     type = ByteRangeHeaderType
 
     @property
     def start(self):
         return self.decoded.start
 
     @property
     def end(self):
         return self.decoded.end
 
     @property
     def total(self):
         return self.decoded.total
 
 
 class StatusHeader(MSRPNamedHeader):
     name = 'Status'
     type = StatusHeaderType
 
     @property
     def code(self):
         return self.decoded.code
 
     @property
     def comment(self):
         return self.decoded.comment
 
 
 class ExpiresHeader(MSRPNamedHeader):
     name = 'Expires'
     type = IntegerHeaderType
 
 
 class MinExpiresHeader(MSRPNamedHeader):
     name = 'Min-Expires'
     type = IntegerHeaderType
 
 
 class MaxExpiresHeader(MSRPNamedHeader):
     name = 'Max-Expires'
     type = IntegerHeaderType
 
 
 class UsePathHeader(MSRPNamedHeader):
     name = 'Use-Path'
     type = URIHeaderType
 
 
 class WWWAuthenticateHeader(MSRPNamedHeader):
     name = 'WWW-Authenticate'
     type = DigestHeaderType
 
 
 class AuthorizationHeader(MSRPNamedHeader):
     name = 'Authorization'
     type = DigestHeaderType
 
 
 class AuthenticationInfoHeader(MSRPNamedHeader):
     name = 'Authentication-Info'
     type = ParameterListHeaderType
 
 
 class ContentTypeHeader(MSRPNamedHeader):
     name = 'Content-Type'
     type = SimpleHeaderType
 
 
 class ContentIDHeader(MSRPNamedHeader):
     name = 'Content-ID'
     type = SimpleHeaderType
 
 
 class ContentDescriptionHeader(MSRPNamedHeader):
     name = 'Content-Description'
     type = SimpleHeaderType
 
 
 class ContentDispositionHeader(MSRPNamedHeader):
     name = 'Content-Disposition'
     type = ContentDispositionHeaderType
 
 
 class UseNicknameHeader(MSRPNamedHeader):
     name = 'Use-Nickname'
     type = UTF8HeaderType
 
 
 class HeaderOrderMapping(dict):
     __levels__ = {
         0: ['To-Path'],
         1: ['From-Path'],
         2: ['Status', 'Message-ID', 'Byte-Range', 'Success-Report', 'Failure-Report'] +
            ['Authorization', 'Authentication-Info', 'WWW-Authenticate', 'Expires', 'Min-Expires', 'Max-Expires', 'Use-Path', 'Use-Nickname'],
         3: ['Content-ID', 'Content-Description', 'Content-Disposition'],
         4: ['Content-Type']
     }
 
     def __init__(self):
         super(HeaderOrderMapping, self).__init__({name: level for level, name_list in self.__levels__.items() for name in name_list})
 
     def __missing__(self, key):
         return 3 if key.startswith('Content-') else 2
 
     sort_key = dict.__getitem__
 
 
 class HeaderOrdering(object):
     name_map = HeaderOrderMapping()
     sort_key = name_map.sort_key
 
 
 class MissingHeader(object):
     decoded = None
 
 
 class MSRPData(object):
     def __init__(self, transaction_id, method=None, code=None, comment=None, headers=None, data='', contflag='$'):
         if method is None and code is None:
             raise ValueError('either method or code must be specified')
         elif method is not None and code is not None:
             raise ValueError('method and code cannot be both specified')
         elif code is None and comment is not None:
             raise ValueError('comment should only be specified when code is specified')
         self.transaction_id = transaction_id
         self.method = method
         self.code = code
         self.comment = comment
         self.headers = headers or {}
         self.data = data
         self.contflag = contflag
         if method is not None:
             self.first_line = 'MSRP {} {}'.format(transaction_id, method)
         elif comment is None:
             self.first_line = 'MSRP {} {:03d}'.format(transaction_id, code)
         else:
             self.first_line = 'MSRP {} {:03d} {}'.format(transaction_id, code, comment)
 
-    def copy(self):
-        return self.__class__(self.transaction_id, self.method, self.code, self.comment, self.headers.copy(), self.data, self.contflag)
-
     def __setattr__(self, name, value):
         if name in {'method', 'code', 'comment'} and name in self.__dict__:
             raise AttributeError('Cannot overwrite attribute')
         if name == 'transaction_id' and name in self.__dict__:
             self.first_line = self.first_line.replace(self.transaction_id, value)
         super(MSRPData, self).__setattr__(name, value)
 
     def __str__(self):  # TODO: make __str__ == encode()?
         return self.first_line
 
     def __repr__(self):
         description = self.first_line
         for name in sorted(self.headers, key=HeaderOrdering.sort_key):
             description += ' {}={!r}'.format(name, self.headers[name].encoded)
         description += ' len={}'.format(self.size)
         return '<{} at {:#x} {} {}>'.format(self.__class__.__name__, id(self), description, self.contflag)
 
     def __eq__(self, other):
         if isinstance(other, MSRPData):
             return self.first_line == other.first_line and self.headers == other.headers and self.data == other.data and self.contflag == other.contflag
         return NotImplemented
 
     def __ne__(self, other):
         return not self == other
 
+    def copy(self):
+        return self.__class__(self.transaction_id, self.method, self.code, self.comment, self.headers.copy(), self.data, self.contflag)
+
     def add_header(self, header):
         self.headers[header.name] = header
 
     def verify_headers(self):
         if 'To-Path' not in self.headers:
             raise HeaderParsingError('To-Path', 'header is missing')
         if 'From-Path' not in self.headers:
             raise HeaderParsingError('From-Path', 'header is missing')
         for header in self.headers.itervalues():
             _ = header.decoded
 
     @property
     def from_path(self):
         return self.headers.get('From-Path', MissingHeader).decoded
 
     @property
     def to_path(self):
         return self.headers.get('To-Path', MissingHeader).decoded
 
     @property
     def content_type(self):
         return self.headers.get('Content-Type', MissingHeader).decoded
 
     @property
     def message_id(self):
         return self.headers.get('Message-ID', MissingHeader).decoded
 
     @property
     def byte_range(self):
         return self.headers.get('Byte-Range', MissingHeader).decoded
 
     @property
     def status(self):
         return self.headers.get('Status', MissingHeader).decoded
 
     @property
     def failure_report(self):
         return self.headers.get('Failure-Report', MissingHeader).decoded or 'yes'
 
     @property
     def success_report(self):
         return self.headers.get('Success-Report', MissingHeader).decoded or 'no'
 
     @property
     def size(self):
         return len(self.data)
 
     def encode_start(self):
         lines = [self.first_line] + ['{}: {}'.format(name, self.headers[name].encoded) for name in sorted(self.headers, key=HeaderOrdering.sort_key)]
         if 'Content-Type' in self.headers:
             lines.append('\r\n')
         return '\r\n'.join(lines)
 
     def encode_end(self, continuation):
         return '\r\n-------%s%s\r\n' % (self.transaction_id, continuation)
 
     def encode(self):
         return self.encode_start() + self.data + self.encode_end(self.contflag)
 
 
 class MSRPProtocol(LineReceiver):
     MAX_LENGTH = 16384
     MAX_LINES = 64
 
     def __init__(self, msrp_transport):
         self.msrp_transport = msrp_transport
         self.term_buf = ''
         self.term_re = None
         self.term_substrings = []
         self._reset()
 
     def _reset(self):
         self._chunk_header = ''
         self.data = None
         self.line_count = 0
 
     def connectionMade(self):
         self.msrp_transport._got_transport(self.transport)
 
     def lineReceived(self, line):
         if self.data:
             if len(line) == 0:
                 terminator = '\r\n-------' + self.data.transaction_id
                 continue_flags = [c+'\r\n' for c in '$#+']
                 self.term_buf = ''
                 self.term_re = re.compile("^(.*)%s([$#+])\r\n(.*)$" % re.escape(terminator), re.DOTALL)
                 self.term_substrings = [terminator[:i] for i in xrange(1, len(terminator)+1)] + [terminator+cont[:i] for cont in continue_flags for i in xrange(1, len(cont))]
                 self.term_substrings.reverse()
 
                 self.msrp_transport.logger.received_new_chunk(self._chunk_header+self.delimiter, self.msrp_transport, chunk=self.data)
                 self.msrp_transport._data_start(self.data)
                 self.setRawMode()
             else:
                 match = self.term_re.match(line)
                 if match:
                     continuation = match.group(1)
                     self.msrp_transport.logger.received_new_chunk(self._chunk_header, self.msrp_transport, chunk=self.data)
                     self.msrp_transport.logger.received_chunk_end(line+self.delimiter, self.msrp_transport, transaction_id=self.data.transaction_id)
                     self.msrp_transport._data_start(self.data)
                     self.msrp_transport._data_end(continuation)
                     self._reset()
                     # This line is only here because it allows the subclass MSRPPRotocol_withLogging
                     # to know that the packet ended. In need of redesign. -Luci
                     self.setLineMode('')
                 else:
                     self._chunk_header += line+self.delimiter
                     self.line_count += 1
                     if self.line_count > self.MAX_LINES:
                         self.msrp_transport.logger.received_illegal_data(self._chunk_header, self.msrp_transport)
                         self._reset()
                         return
                     try:
                         name, value = line.split(': ', 1)
                     except ValueError:
                         return # let this pass silently, we'll just not read this line
                     else:
                         self.data.add_header(MSRPHeader(name, value))
         else: # we received a new message
             try:
                 msrp, transaction_id, rest = line.split(" ", 2)
             except ValueError:
                 self.msrp_transport.logger.received_illegal_data(line+self.delimiter, self.msrp_transport)
                 return # drop connection?
             if msrp != "MSRP":
                 self.msrp_transport.logger.received_illegal_data(line+self.delimiter, self.msrp_transport)
                 return # drop connection?
             method, code, comment = None, None, None
             rest_sp = rest.split(" ", 1)
             try:
                 if len(rest_sp[0]) != 3:
                     raise ValueError
                 code = int(rest_sp[0])
             except ValueError: # we have a request
                 method = rest_sp[0]
             else: # we have a response
                 if len(rest_sp) > 1:
                     comment = rest_sp[1]
             self.data = MSRPData(transaction_id, method, code, comment)
             self.term_re = re.compile("^-------%s([$#+])$" % re.escape(transaction_id))
             self._chunk_header = line+self.delimiter
 
     def lineLengthExceeded(self, line):
         self._reset()
 
     def rawDataReceived(self, data):
         data = self.term_buf + data
         match = self.term_re.match(data)
         if match: # we got the last data for this message
             contents, continuation, extra = match.groups()
             if contents:
                 self.msrp_transport.logger.received_chunk_data(contents, self.msrp_transport, transaction_id=self.data.transaction_id)
                 self.msrp_transport._data_write(contents, final=True)
             self.msrp_transport.logger.received_chunk_end('\r\n-------%s%s\r\n' % (self.data.transaction_id, continuation), self.msrp_transport, transaction_id=self.data.transaction_id)
             self.msrp_transport._data_end(continuation)
             self._reset()
             self.setLineMode(extra)
         else:
             for term in self.term_substrings:
                 if data.endswith(term):
                     self.term_buf = data[-len(term):]
                     data = data[:-len(term)]
                     break
             else:
                 self.term_buf = ''
             self.msrp_transport.logger.received_chunk_data(data, self.msrp_transport, transaction_id=self.data.transaction_id)
             self.msrp_transport._data_write(data, final=False)
 
     def connectionLost(self, reason=connectionDone):
         self.msrp_transport._connectionLost(reason)
 
 
 _re_uri = re.compile("^(?P<scheme>.*?)://(((?P<user>.*?)@)?(?P<host>.*?)(:(?P<port>[0-9]+?))?)(/(?P<session_id>.*?))?;(?P<transport>.*?)(;(?P<parameters>.*))?$")
 def parse_uri(uri_str):
     match = _re_uri.match(uri_str)
     if match is None:
         raise ParsingError("Cannot parse URI")
     uri_params = match.groupdict()
     if uri_params["port"] is not None:
         uri_params["port"] = int(uri_params["port"])
     if uri_params["parameters"] is not None:
         try:
             uri_params["parameters"] = dict(param.split("=") for param in uri_params["parameters"].split(";"))
         except ValueError:
             raise ParsingError("Cannot parse URI parameters")
     scheme = uri_params.pop("scheme")
     if scheme == "msrp":
         uri_params["use_tls"] = False
     elif scheme == "msrps":
         uri_params["use_tls"] = True
     else:
         raise ParsingError("Invalid scheme user in URI: %s" % scheme)
     if uri_params["transport"] != "tcp":
         raise ParsingError('Invalid transport in URI, only "tcp" is accepted: %s' % uri_params["transport"])
     return URI(**uri_params)
 
 class ConnectInfo(object):
     host = None
     use_tls = True
     port = 2855
 
     def __init__(self, host=None, use_tls=None, port=None, credentials=None):
         if host is not None:
             self.host = host
         if use_tls is not None:
             self.use_tls = use_tls
         if port is not None:
             self.port = port
         self.credentials = credentials
         if self.use_tls and self.credentials is None:
             from gnutls.interfaces.twisted import X509Credentials
             self.credentials = X509Credentials(None, None)
 
     @property
     def scheme(self):
         if self.use_tls:
             return 'msrps'
         else:
             return 'msrp'
 
 
 # use TLS_URI and TCP_URI ?
 class URI(ConnectInfo):
 
     def __init__(self, host=None, use_tls=None, user=None, port=None,
                  session_id=None, transport="tcp", parameters=None,
                  credentials=None):
         ConnectInfo.__init__(self, host or host_module.default_ip, use_tls=use_tls, port=port, credentials=credentials)
         self.user = user
         if session_id is None:
             session_id = '%x' % random.getrandbits(80)
         self.session_id = session_id
         self.transport = transport
         if parameters is None:
             self.parameters = {}
         else:
             self.parameters = parameters
 
     def __repr__(self):
         params = [self.host, self.use_tls, self.user, self.port, self.session_id, self.transport, self.parameters]
         defaults = [False, None, None, None, 'tcp', {}]
         while defaults and params[-1]==defaults[-1]:
             del params[-1]
             del defaults[-1]
         return '%s(%s)' % (self.__class__.__name__, ', '.join(`x` for x in params))
 
     def __str__(self):
         uri_str = []
         if self.use_tls:
             uri_str.append("msrps://")
         else:
             uri_str.append("msrp://")
         if self.user:
             uri_str.extend([self.user, "@"])
         uri_str.append(self.host)
         if self.port:
             uri_str.extend([":", str(self.port)])
         if self.session_id:
             uri_str.extend(["/", self.session_id])
         uri_str.extend([";", self.transport])
         for key, value in self.parameters.iteritems():
             uri_str.extend([";", key, "=", value])
         return "".join(uri_str)
 
     def __eq__(self, other):
         """MSRP URI comparison according to section 6.1 of RFC 4975"""
         if self is other:
             return True
         try:
             if self.use_tls != other.use_tls:
                 return False
             if self.host.lower() != other.host.lower():
                 return False
             if self.port != other.port:
                 return False
             if self.session_id != other.session_id:
                 return False
             if self.transport.lower() != other.transport.lower():
                 return False
         except AttributeError:
             return False
         return True
 
     def __ne__(self, other):
         return not self == other
 
     def __hash__(self):
         return hash((self.use_tls, self.host.lower(), self.port, self.session_id, self.transport.lower()))