diff --git a/msrp/backend/sipthor.py b/msrp/backend/sipthor.py
index 46f07f6..ff400bd 100644
--- a/msrp/backend/sipthor.py
+++ b/msrp/backend/sipthor.py
@@ -1,127 +1,129 @@
 
 import cjson
 import signal
 
 from application import log
 from application.configuration import ConfigSection, ConfigSetting
 from application.python.types import Singleton
 from application.system import host
 from application.process import process
 from gnutls.interfaces.twisted import TLSContext, X509Credentials
 from sqlobject import sqlhub, connectionForURI, SQLObject, StringCol, BLOBCol
 from sqlobject.dberrors import Error as SQLObjectError
 from twisted.internet.threads import deferToThread
 
 from msrp import configuration_filename, __version__
 from msrp.digest import LoginFailed
 from msrp.tls import Certificate, PrivateKey
 
 from thor.eventservice import EventServiceClient, ThorEvent
 from thor.entities import ThorEntitiesRoleMap, GenericThorEntity as ThorEntity
 from thor.tls import X509NameValidator
 
 
 class Config(ConfigSection):
     __cfgfile__ = configuration_filename
     __section__ = 'SIPThor'
 
     cleartext_passwords = True
     uri = "mysql://user:pass@db/sipthor"
     subscriber_table = "sip_accounts"
     username_col = "username"
     domain_col = "domain"
     profile_col = "profile"
     multiply = 1000
     certificate = ConfigSetting(type=Certificate, value=None)
     private_key = ConfigSetting(type=PrivateKey, value=None)
     ca = ConfigSetting(type=Certificate, value=None)
 
+
 class ThorNetworkConfig(ConfigSection):
     __cfgfile__ = configuration_filename
     __section__ = 'ThorNetwork'
 
     domain = "sipthor-domain"
     passport = X509NameValidator('O:undefined, OU:undefined')
 
 
 class Subscribers(SQLObject):
     class sqlmeta:
         table = Config.subscriber_table
-    username = StringCol(dbName = Config.username_col)
-    domain = StringCol(dbName = Config.domain_col)
-    profile = BLOBCol(dbName = Config.profile_col)
+    username = StringCol(dbName=Config.username_col)
+    domain = StringCol(dbName=Config.domain_col)
+    profile = BLOBCol(dbName=Config.profile_col)
+
 
 sqlhub.processConnection = connectionForURI(Config.uri)
 
 
 class ThorNetworkService(EventServiceClient):
     __metaclass__ = Singleton
     topics = ["Thor.Members"]
 
     def __init__(self):
         self.node = ThorEntity(host.default_ip, ['msrprelay_server'], version=__version__)
         self.networks = {}
         self.presence_message = ThorEvent('Thor.Presence', self.node.id)
         self.shutdown_message = ThorEvent('Thor.Leave', self.node.id)
         credentials = X509Credentials(Config.certificate, Config.private_key, [Config.ca])
         credentials.verify_peer = True
         tls_context = TLSContext(credentials)
         EventServiceClient.__init__(self, ThorNetworkConfig.domain, tls_context)
         process.signals.add_handler(signal.SIGHUP, self._handle_SIGHUP)
         process.signals.add_handler(signal.SIGINT, self._handle_SIGINT)
         process.signals.add_handler(signal.SIGTERM, self._handle_SIGTERM)
 
     def handle_event(self, event):
         # print "Received event: %s" % event
         networks = self.networks
-        role_map = ThorEntitiesRoleMap(event.message) ## mapping between role names and lists of nodes with that role
+        role_map = ThorEntitiesRoleMap(event.message)  # mapping between role names and lists of nodes with that role
         for role in ["msrprelay_server"]:
             try:
-                network = networks[role] ## avoid setdefault here because it always evaluates the 2nd argument
+                network = networks[role]  # avoid setdefault here because it always evaluates the 2nd argument
             except KeyError:
                 from thor import network as thor_network
                 network = thor_network.new(Config.multiply)
                 networks[role] = network
             new_nodes = set([node.ip for node in role_map.get(role, [])])
             old_nodes = set(network.nodes)
             added_nodes = new_nodes - old_nodes
             removed_nodes = old_nodes - new_nodes
             if removed_nodes:
                 for node in removed_nodes:
                     network.remove_node(node)
                 plural = len(removed_nodes) != 1 and 's' or ''
                 log.msg("removed %s node%s: %s" % (role, plural, ', '.join(removed_nodes)))
             if added_nodes:
                 for node in added_nodes:
                     network.add_node(node)
                 plural = len(added_nodes) != 1 and 's' or ''
                 log.msg("added %s node%s: %s" % (role, plural, ', '.join(added_nodes)))
-            #print "Thor %s nodes: %s" % (role, str(network.nodes))
+            # print "Thor %s nodes: %s" % (role, str(network.nodes))
 
 
 class Checker(object):
     def __init__(self):
         self.cleartext_passwords = Config.cleartext_passwords
         self._thor_service = ThorNetworkService()
 
     def _retrieve(self, col, username, domain):
         try:
             subscriber = Subscribers.selectBy(username=username, domain=domain)[0]
         except IndexError:
             raise LoginFailed("Username not found")
         except SQLObjectError:
             raise LoginFailed("Database error")
         try:
             profile = cjson.decode(subscriber.profile)
         except cjson.DecodeError:
             raise LoginFailed("Database JSON error")
         try:
             return profile[col]
         except KeyError:
             raise LoginFailed("Database profile error")
 
     def retrieve_password(self, username, domain):
         return deferToThread(self._retrieve, "password", username, domain)
 
     def retrieve_ha1(self, username, domain):
         return deferToThread(self._retrieve, "ha1", username, domain)