diff --git a/src/common/stanza_session.py b/src/common/stanza_session.py
index ee4b844c5..2a17f8d0b 100644
--- a/src/common/stanza_session.py
+++ b/src/common/stanza_session.py
@@ -73,10 +73,12 @@ class StanzaSession(object):
 	def remove_events(self, types):
 		any_removed = False
 
-		for event in gajim.events.get_events(self.conn.name, self.jid, types=types):
+		for event in gajim.events.get_events(self.conn.name, self.jid,
+		types=types):
 			# the event wasn't in this session
 			if (event.type_ == 'chat' and event.parameters[8] != self) or \
-			(event.type_ == 'printed_chat' and event.parameters[0].session != self):
+			(event.type_ == 'printed_chat' and event.parameters[0].session != \
+			self):
 				continue
 
 			# events.remove_events returns True when there were no events
@@ -89,7 +91,8 @@ class StanzaSession(object):
 		return any_removed
 
 	def generate_thread_id(self):
-		return "".join([random.choice(string.ascii_letters) for x in xrange(0,32)])
+		return ''.join([random.choice(string.ascii_letters) for x in xrange(0,
+			32)])
 
 	def send(self, msg):
 		if self.thread_id:
@@ -101,7 +104,7 @@ class StanzaSession(object):
 		if isinstance(msg, xmpp.Message):
 			self.last_send = time.time()
 
-	def reject_negotiation(self, body = None):
+	def reject_negotiation(self, body=None):
 		msg = xmpp.Message()
 		feature = msg.NT.feature
 		feature.setNamespace(xmpp.NS_FEATURE)
@@ -120,7 +123,8 @@ class StanzaSession(object):
 		self.cancelled_negotiation()
 
 	def cancelled_negotiation(self):
-		'''A negotiation has been cancelled, so reset this session to its default state.'''
+		'''A negotiation has been cancelled, so reset this session to its default
+		state.'''
 
 		if self.control:
 			self.control.on_cancel_session_negotiation()
@@ -185,8 +189,8 @@ if gajim.HAVE_PYCRYPTO:
 #	handle_session_negotiation method.
 
 class EncryptedStanzaSession(StanzaSession):
-	def __init__(self, conn, jid, thread_id, type = 'chat'):
-		StanzaSession.__init__(self, conn, jid, thread_id, type = 'chat')
+	def __init__(self, conn, jid, thread_id, type='chat'):
+		StanzaSession.__init__(self, conn, jid, thread_id, type='chat')
 
 		self.xes = {}
 		self.es = {}
@@ -286,13 +290,13 @@ class EncryptedStanzaSession(StanzaSession):
 
 	def generate_initiator_keys(self, k):
 		return (self.hmac(k, 'Initiator Cipher Key'),
-						self.hmac(k, 'Initiator MAC Key'),
-						self.hmac(k, 'Initiator SIGMA Key')		 )
+			self.hmac(k, 'Initiator MAC Key'),
+			self.hmac(k, 'Initiator SIGMA Key'))
 
 	def generate_responder_keys(self, k):
 		return (self.hmac(k, 'Responder Cipher Key'),
-						self.hmac(k, 'Responder MAC Key'),
-						self.hmac(k, 'Responder SIGMA Key')		)
+			self.hmac(k, 'Responder MAC Key'),
+			self.hmac(k, 'Responder SIGMA Key'))
 
 	def compress(self, plaintext):
 		if self.compression is None:
@@ -336,7 +340,8 @@ class EncryptedStanzaSession(StanzaSession):
 		try:
 			parsed = xmpp.Node(node='<node>' + plaintext + '</node>')
 		except:
-			raise exceptions.DecryptionError, 'decrypted <data/> not parseable as XML'
+			raise exceptions.DecryptionError,
+				'decrypted <data/> not parseable as XML'
 
 		for child in parsed.getChildren():
 			stanza.addChild(node=child)
@@ -348,13 +353,13 @@ class EncryptedStanzaSession(StanzaSession):
 
 	def logging_preference(self):
 		if gajim.config.get('log_encrypted_sessions'):
-			return ["may", "mustnot"]
+			return ['may', 'mustnot']
 		else:
-			return ["mustnot", "may"]
+			return ['mustnot', 'may']
 
 	def get_shared_secret(self, e, y, p):
 		if (not 1 < e < (p - 1)):
-			raise exceptions.NegotiationError, "invalid DH value"
+			raise exceptions.NegotiationError, 'invalid DH value'
 
 		return crypto.sha256(crypto.encode_mpi(crypto.powmod(e, y, p)))
 
@@ -370,7 +375,8 @@ class EncryptedStanzaSession(StanzaSession):
 		m_o_calculated = self.hmac(self.km_o, crypto.encode_mpi(self.c_o) + id_o)
 
 		if m_o_calculated != m_o:
-			raise exceptions.NegotiationError, 'calculated m_%s differs from received m_%s' % (i_o, i_o)
+			raise exceptions.NegotiationError,
+				'calculated m_%s differs from received m_%s' % (i_o, i_o)
 
 		if i_o == 'a' and self.sas_algs == 'sas28x5':
 			# we don't need to calculate this if there's a verified retained secret
@@ -401,7 +407,7 @@ class EncryptedStanzaSession(StanzaSession):
 
 			enc_sig = parsed.getTag(name='SignatureValue',
 				namespace=XmlDsig).getData()
-			signature = (crypto.decode_mpi(base64.b64decode(enc_sig)),)
+			signature = (crypto.decode_mpi(base64.b64decode(enc_sig)), )
 		else:
 			mac_o = self.decrypt(id_o)
 			pubkey_o = ''
@@ -423,10 +429,12 @@ class EncryptedStanzaSession(StanzaSession):
 			hash = crypto.sha256(mac_o_calculated)
 
 			if not eir_pubkey.verify(hash, signature):
-				raise exceptions.NegotiationError, 'public key signature verification failed!'
+				raise exceptions.NegotiationError,
+					'public key signature verification failed!'
 
 		elif mac_o_calculated != mac_o:
-			raise exceptions.NegotiationError, 'calculated mac_%s differs from received mac_%s' % (i_o, i_o)
+			raise exceptions.NegotiationError,
+				'calculated mac_%s differs from received mac_%s' % (i_o, i_o)
 
 	def make_identity(self, form, dh_i):
 		if self.negotiated['send_pubkey']:
@@ -434,23 +442,28 @@ class EncryptedStanzaSession(StanzaSession):
 				pubkey = secrets.secrets().my_pubkey(self.conn.name)
 				fields = (pubkey.n, pubkey.e)
 
-				cb_fields = map(lambda f: base64.b64encode(crypto.encode_mpi(f)), fields)
+				cb_fields = map(lambda f: base64.b64encode(crypto.encode_mpi(f)),
+					fields)
 
-				pubkey_s = '<RSAKeyValue xmlns="http://www.w3.org/2000/09/xmldsig#"><Modulus>%s</Modulus><Exponent>%s</Exponent></RSAKeyValue>' % tuple(cb_fields)
+				pubkey_s = '<RSAKeyValue xmlns="http://www.w3.org/2000/09/xmldsig#"'
+					'><Modulus>%s</Modulus><Exponent>%s</Exponent></RSAKeyValue>' % \
+					tuple(cb_fields)
 		else:
 			pubkey_s = ''
 
 		form_s2 = ''.join(map(lambda el: xmpp.c14n.c14n(el), form.getChildren()))
 
 		old_c_s = self.c_s
-		content = self.n_o + self.n_s + crypto.encode_mpi(dh_i) + pubkey_s + self.form_s + form_s2
+		content = self.n_o + self.n_s + crypto.encode_mpi(dh_i) + pubkey_s + \
+			self.form_s + form_s2
 
 		mac_s = self.hmac(self.ks_s, content)
 
 		if self.negotiated['send_pubkey']:
 			signature = self.sign(mac_s)
 
-			sign_s = '<SignatureValue xmlns="http://www.w3.org/2000/09/xmldsig#">%s</SignatureValue>' % base64.b64encode(signature)
+			sign_s = '<SignatureValue xmlns="http://www.w3.org/2000/09/xmldsig#">'
+				'%s</SignatureValue>' % base64.b64encode(signature)
 
 			if self.negotiated['send_pubkey'] == 'hash':
 				b64ed = base64.b64encode(self.hash(pubkey_s))
@@ -471,8 +484,8 @@ class EncryptedStanzaSession(StanzaSession):
 				# XXX save retained secret?
 				self.check_identity(lambda : ())
 
-		return (xmpp.DataField(name='identity', value=base64.b64encode(id_s)), \
-						xmpp.DataField(name='mac', value=base64.b64encode(m_s)))
+		return (xmpp.DataField(name='identity', value=base64.b64encode(id_s)),
+			xmpp.DataField(name='mac', value=base64.b64encode(m_s)))
 
 	def negotiate_e2e(self, sigmai):
 		self.negotiated = {}
@@ -483,41 +496,58 @@ class EncryptedStanzaSession(StanzaSession):
 
 		x = xmpp.DataForm(typ='form')
 
-		x.addChild(node=xmpp.DataField(name='FORM_TYPE', value='urn:xmpp:ssn', typ='hidden'))
-		x.addChild(node=xmpp.DataField(name='accept', value='1', typ='boolean', required=True))
+		x.addChild(node=xmpp.DataField(name='FORM_TYPE', value='urn:xmpp:ssn',
+			typ='hidden'))
+		x.addChild(node=xmpp.DataField(name='accept', value='1', typ='boolean',
+			required=True))
 
 		# this field is incorrectly called 'otr' in XEPs 0116 and 0217
-		x.addChild(node=xmpp.DataField(name='logging', typ='list-single', options=self.logging_preference(), required=True))
+		x.addChild(node=xmpp.DataField(name='logging', typ='list-single',
+			options=self.logging_preference(), required=True))
 
 		# unsupported options: 'disabled', 'enabled'
-		x.addChild(node=xmpp.DataField(name='disclosure', typ='list-single', options=['never'], required=True))
-		x.addChild(node=xmpp.DataField(name='security', typ='list-single', options=['e2e'], required=True))
-		x.addChild(node=xmpp.DataField(name='crypt_algs', value='aes128-ctr', typ='hidden'))
-		x.addChild(node=xmpp.DataField(name='hash_algs', value='sha256', typ='hidden'))
-		x.addChild(node=xmpp.DataField(name='compress', value='none', typ='hidden'))
+		x.addChild(node=xmpp.DataField(name='disclosure', typ='list-single',
+			options=['never'], required=True))
+		x.addChild(node=xmpp.DataField(name='security', typ='list-single',
+			options=['e2e'], required=True))
+		x.addChild(node=xmpp.DataField(name='crypt_algs', value='aes128-ctr',
+			typ='hidden'))
+		x.addChild(node=xmpp.DataField(name='hash_algs', value='sha256',
+			typ='hidden'))
+		x.addChild(node=xmpp.DataField(name='compress', value='none',
+			typ='hidden'))
 
 		# unsupported options: 'iq', 'presence'
-		x.addChild(node=xmpp.DataField(name='stanzas', typ='list-multi', options=['message']))
+		x.addChild(node=xmpp.DataField(name='stanzas', typ='list-multi',
+			options=['message']))
 
-		x.addChild(node=xmpp.DataField(name='init_pubkey', options=['none', 'key', 'hash'], typ='list-single'))
+		x.addChild(node=xmpp.DataField(name='init_pubkey', options=['none', 'key',
+			'hash'], typ='list-single'))
 
 		# XXX store key, use hash
-		x.addChild(node=xmpp.DataField(name='resp_pubkey', options=['none', 'key'], typ='list-single'))
+		x.addChild(node=xmpp.DataField(name='resp_pubkey', options=['none',
+			'key'], typ='list-single'))
 
 		x.addChild(node=xmpp.DataField(name='ver', value='1.0', typ='hidden'))
 
-		x.addChild(node=xmpp.DataField(name='rekey_freq', value='4294967295', typ='hidden'))
+		x.addChild(node=xmpp.DataField(name='rekey_freq', value='4294967295',
+			typ='hidden'))
 
-		x.addChild(node=xmpp.DataField(name='sas_algs', value='sas28x5', typ='hidden'))
-		x.addChild(node=xmpp.DataField(name='sign_algs', value='http://www.w3.org/2000/09/xmldsig#rsa-sha256', typ='hidden'))
+		x.addChild(node=xmpp.DataField(name='sas_algs', value='sas28x5',
+			typ='hidden'))
+		x.addChild(node=xmpp.DataField(name='sign_algs',
+			value='http://www.w3.org/2000/09/xmldsig#rsa-sha256', typ='hidden'))
 
 		self.n_s = crypto.generate_nonce()
 
-		x.addChild(node=xmpp.DataField(name='my_nonce', value=base64.b64encode(self.n_s), typ='hidden'))
+		x.addChild(node=xmpp.DataField(name='my_nonce',
+			value=base64.b64encode(self.n_s), typ='hidden'))
 
-		modp_options = [ int(g) for g in gajim.config.get('esession_modp').split(',') ]
+		modp_options = [ int(g) for g in gajim.config.get('esession_modp').split(
+			',') ]
 
-		x.addChild(node=xmpp.DataField(name='modp', typ='list-single', options=map(lambda x: [ None, x ], modp_options)))
+		x.addChild(node=xmpp.DataField(name='modp', typ='list-single',
+			options=map(lambda x: [ None, x ], modp_options)))
 
 		x.addChild(node=self.make_dhfield(modp_options, sigmai))
 		self.sigmai = sigmai
@@ -536,16 +566,10 @@ class EncryptedStanzaSession(StanzaSession):
 		not_acceptable = []
 		ask_user = {}
 
-		fixed = { 'disclosure': 'never',
-								'security': 'e2e',
-							'crypt_algs': 'aes128-ctr',
-							'hash_algs': 'sha256',
-								'compress': 'none',
-								'stanzas': 'message',
-						'init_pubkey': 'none',
-						'resp_pubkey': 'none',
-										'ver': '1.0',
-								'sas_algs': 'sas28x5' }
+		fixed = { 'disclosure': 'never', 'security': 'e2e',
+			'crypt_algs': 'aes128-ctr', 'hash_algs': 'sha256', 'compress': 'none',
+			'stanzas': 'message', 'init_pubkey': 'none', 'resp_pubkey': 'none',
+			'ver': '1.0', 'sas_algs': 'sas28x5' }
 
 		self.encryptable_stanzas = ['message']
 
@@ -554,7 +578,8 @@ class EncryptedStanzaSession(StanzaSession):
 		self.hash_alg = SHA256
 		self.compression = None
 
-		for name, field in map(lambda name: (name, form.getField(name)), form.asDict().keys()):
+		for name, field in map(lambda name: (name, form.getField(name)),
+		form.asDict().keys()):
 			options = map(lambda x: x[1], field.getOptions())
 			values = field.getValues()
 
@@ -598,7 +623,8 @@ class EncryptedStanzaSession(StanzaSession):
 				if (XmlDsig + 'rsa-sha256') in options:
 					negotiated['sign_algs'] = XmlDsig + 'rsa-sha256'
 			else:
-				# XXX some things are handled elsewhere, some things are not-implemented
+				# XXX some things are handled elsewhere, some things are
+				# not-implemented
 				pass
 
 		return (negotiated, not_acceptable, ask_user)
@@ -632,28 +658,31 @@ class EncryptedStanzaSession(StanzaSession):
 		self.n_o = base64.b64decode(form['my_nonce'])
 
 		dhhashes = form.getField('dhhashes').getValues()
-		self.negotiated['He'] = base64.b64decode(dhhashes[group_order].encode("utf8"))
+		self.negotiated['He'] = base64.b64decode(dhhashes[group_order].encode(
+			'utf8'))
 
 		bytes = int(self.n / 8)
 
 		self.n_s = crypto.generate_nonce()
 
-		self.c_o = crypto.decode_mpi(crypto.random_bytes(bytes)) # n-bit random number
+		# n-bit random number
+		self.c_o = crypto.decode_mpi(crypto.random_bytes(bytes))
 		self.c_s = self.c_o ^ (2 ** (self.n - 1))
 
 		self.y = crypto.srand(2 ** (2 * self.n - 1), p - 1)
 		self.d = crypto.powmod(g, self.y, p)
 
-		to_add = { 'my_nonce': self.n_s,
-						'dhkeys': crypto.encode_mpi(self.d),
-						'counter': crypto.encode_mpi(self.c_o),
-						'nonce': self.n_o }
+		to_add = {'my_nonce': self.n_s,
+			'dhkeys': crypto.encode_mpi(self.d),
+			'counter': crypto.encode_mpi(self.c_o),
+			'nonce': self.n_o}
 
 		for name in to_add:
 			b64ed = base64.b64encode(to_add[name])
 			x.addChild(node=xmpp.DataField(name=name, value=b64ed))
 
-		self.form_o = ''.join(map(lambda el: xmpp.c14n.c14n(el), form.getChildren()))
+		self.form_o = ''.join(map(lambda el: xmpp.c14n.c14n(el),
+			form.getChildren()))
 		self.form_s = ''.join(map(lambda el: xmpp.c14n.c14n(el), x.getChildren()))
 
 		self.status = 'responded-e2e'
@@ -687,14 +716,15 @@ class EncryptedStanzaSession(StanzaSession):
 		else:
 			negotiated['logging'] = self.logging_preference()[0]
 
-		for r,a in (('recv_pubkey', 'resp_pubkey'), ('send_pubkey', 'init_pubkey')):
+		for r,a in (('recv_pubkey', 'resp_pubkey'), ('send_pubkey',
+		'init_pubkey')):
 			negotiated[r] = None
 
 			if a in form.asDict() and form[a] in ('key', 'hash'):
 				negotiated[r] = form[a]
 
 		if 'sign_algs' in form.asDict():
-			if form['sign_algs'] in (XmlDsig + 'rsa-sha256',):
+			if form['sign_algs'] in (XmlDsig + 'rsa-sha256', ):
 				negotiated['sign_algs'] = form['sign_algs']
 			else:
 				not_acceptable.append(form['sign_algs'])
@@ -731,9 +761,11 @@ class EncryptedStanzaSession(StanzaSession):
 
 		self.k = self.get_shared_secret(self.d, x, p)
 
-		result.addChild(node=xmpp.DataField(name='FORM_TYPE', value='urn:xmpp:ssn'))
+		result.addChild(node=xmpp.DataField(name='FORM_TYPE',
+			value='urn:xmpp:ssn'))
 		result.addChild(node=xmpp.DataField(name='accept', value='1'))
-		result.addChild(node=xmpp.DataField(name='nonce', value=base64.b64encode(self.n_o)))
+		result.addChild(node=xmpp.DataField(name='nonce',
+			value=base64.b64encode(self.n_o)))
 
 		self.kc_s, self.km_s, self.ks_s = self.generate_initiator_keys(self.k)
 
@@ -741,7 +773,8 @@ class EncryptedStanzaSession(StanzaSession):
 			self.kc_o, self.km_o, self.ks_o = self.generate_responder_keys(self.k)
 			self.verify_identity(form, self.d, True, 'b')
 		else:
-			srses = secrets.secrets().retained_secrets(self.conn.name, self.jid.getStripped())
+			srses = secrets.secrets().retained_secrets(self.conn.name,
+				self.jid.getStripped())
 			rshashes = [self.hmac(self.n_s, rs) for (rs,v) in srses]
 
 			if not rshashes:
@@ -751,11 +784,14 @@ class EncryptedStanzaSession(StanzaSession):
 
 			rshashes = [base64.b64encode(rshash) for rshash in rshashes]
 			result.addChild(node=xmpp.DataField(name='rshashes', value=rshashes))
-			result.addChild(node=xmpp.DataField(name='dhkeys', value=base64.b64encode(crypto.encode_mpi(e))))
+			result.addChild(node=xmpp.DataField(name='dhkeys',
+				value=base64.b64encode(crypto.encode_mpi(e))))
 
-			self.form_o = ''.join(map(lambda el: xmpp.c14n.c14n(el), form.getChildren()))
+			self.form_o = ''.join(map(lambda el: xmpp.c14n.c14n(el),
+				form.getChildren()))
 
-		# MUST securely destroy K unless it will be used later to generate the final shared secret
+		# MUST securely destroy K unless it will be used later to generate the
+		# final shared secret
 
 		for datafield in self.make_identity(result, e):
 			result.addChild(node=datafield)
@@ -779,7 +815,8 @@ class EncryptedStanzaSession(StanzaSession):
 		x = xmpp.DataForm(typ='result')
 
 		for field in ('nonce', 'dhkeys', 'rshashes', 'identity', 'mac'):
-			assert field in form.asDict(), "alice's form didn't have a %s field" % field
+			assert field in form.asDict(), "alice's form didn't have a %s field" \
+				% field
 
 		# 4.5.1 generating provisory session keys
 		e = crypto.decode_mpi(base64.b64decode(form['dhkeys']))
@@ -800,8 +837,10 @@ class EncryptedStanzaSession(StanzaSession):
 
 		srs = ''
 
-		srses = secrets.secrets().retained_secrets(self.conn.name, self.jid.getStripped())
-		rshashes = [base64.b64decode(rshash) for rshash in form.getField('rshashes').getValues()]
+		srses = secrets.secrets().retained_secrets(self.conn.name,
+			self.jid.getStripped())
+		rshashes = [base64.b64decode(rshash) for rshash in form.getField(
+			'rshashes').getValues()]
 
 		for (secret, verified) in srses:
 			if self.hmac(self.n_o, secret) in rshashes:
@@ -824,8 +863,10 @@ class EncryptedStanzaSession(StanzaSession):
 			srshash = crypto.random_bytes(32)
 
 		x.addChild(node=xmpp.DataField(name='FORM_TYPE', value='urn:xmpp:ssn'))
-		x.addChild(node=xmpp.DataField(name='nonce', value=base64.b64encode(self.n_o)))
-		x.addChild(node=xmpp.DataField(name='srshash', value=base64.b64encode(srshash)))
+		x.addChild(node=xmpp.DataField(name='nonce', value=base64.b64encode(
+			self.n_o)))
+		x.addChild(node=xmpp.DataField(name='srshash', value=base64.b64encode(
+			srshash)))
 
 		for datafield in self.make_identity(x, self.d):
 			x.addChild(node=datafield)
@@ -847,7 +888,8 @@ class EncryptedStanzaSession(StanzaSession):
 
 	def final_steps_alice(self, form):
 		srs = ''
-		srses = secrets.secrets().retained_secrets(self.conn.name, self.jid.getStripped())
+		srses = secrets.secrets().retained_secrets(self.conn.name,
+			self.jid.getStripped())
 
 		srshash = base64.b64decode(form['srshash'])
 
@@ -869,7 +911,8 @@ class EncryptedStanzaSession(StanzaSession):
 		# 4.6.2 Verifying Bob's Identity
 
 		self.verify_identity(form, self.d, False, 'b')
-		# Note: If Alice discovers an error then she SHOULD ignore any encrypted content she received in the stanza.
+		# Note: If Alice discovers an error then she SHOULD ignore any encrypted
+		# content she received in the stanza.
 
 		if self.negotiated['logging'] == 'mustnot':
 			self.loggable = False
@@ -881,7 +924,9 @@ class EncryptedStanzaSession(StanzaSession):
 			self.control.print_esession_details()
 
 	def do_retained_secret(self, k, old_srs):
-		'''calculate the new retained secret. determine if the user needs to check the remote party's identity. set up callbacks for when the identity has been verified.'''
+		'''calculate the new retained secret. determine if the user needs to check
+		the remote party's identity. set up callbacks for when the identity has
+		been verified.'''
 
 		new_srs = self.hmac(k, 'New Retained Secret')
 		self.srs = new_srs
@@ -899,16 +944,19 @@ class EncryptedStanzaSession(StanzaSession):
 				self.verified_identity = True
 			else:
 				# had a secret, but it wasn't verified.
-				secrets.secrets().replace_srs(account, bjid, old_srs, new_srs, False)
+				secrets.secrets().replace_srs(account, bjid, old_srs, new_srs,
+					False)
 		else:
 			# we don't even have an SRS
 			secrets.secrets().save_new_srs(account, bjid, new_srs, False)
 
 	def _verified_srs_cb(self):
-		secrets.secrets().replace_srs(self.conn.name, self.jid.getStripped(), self.srs, self.srs, True)
+		secrets.secrets().replace_srs(self.conn.name, self.jid.getStripped(),
+			self.srs, self.srs, True)
 
 	def _unverified_srs_cb(self):
-		secrets.secrets().replace_srs(self.conn.name, self.jid.getStripped(), self.srs, self.srs, False)
+		secrets.secrets().replace_srs(self.conn.name, self.jid.getStripped(),
+			self.srs, self.srs, False)
 
 	def make_dhfield(self, modp_options, sigmai):
 		dhs = []