--- a/src/memory/disco.py	Tue Aug 25 16:51:00 2015 +0200
+++ b/src/memory/disco.py	Tue Aug 25 16:52:18 2015 +0200
@@ -25,6 +25,7 @@
 from twisted.words.protocols.jabber.error import StanzaError
 from twisted.internet import defer
 from twisted.internet import reactor
+from twisted.python import failure
 from sat.core.constants import Const as C
 from wokkel import disco
 from base64 import b64encode
@@ -86,7 +87,7 @@
         """
         disco_infos = yield self.getInfos(jid_, profile_key)
         if not feature in disco_infos.features:
-            raise exceptions.FeatureNotFound
+            raise failure.Failure(exceptions.FeatureNotFound)
 
     @defer.inlineCallbacks
     def checkFeatures(self, features, jid_=None, identity=None, profile_key=C.PROF_KEY_NONE):
@@ -101,10 +102,10 @@
         """
         disco_infos = yield self.getInfos(jid_, profile_key)
         if not set(features).issubset(disco_infos.features):
-            raise exceptions.FeatureNotFound
+            raise failure.Failure(exceptions.FeatureNotFound())
 
         if identity is not None and identity not in disco_infos.identities:
-            raise exceptions.FeatureNotFound
+            raise failure.Failure(exceptions.FeatureNotFound())
 
     def getInfos(self, jid_=None, profile_key=C.PROF_KEY_NONE):
         """get disco infos from jid_, filling capability hash if needed
@@ -158,10 +159,10 @@
         defer.returnValue(items)
 
 
-    def _infosEb(self, failure, entity_jid):
-        failure.trap(StanzaError)
+    def _infosEb(self, failure_, entity_jid):
+        failure_.trap(StanzaError)
         log.warning(_(u"Error while requesting [%(jid)s]: %(error)s") % {'jid': entity_jid.full(),
-                                                                    'error': failure.getErrorMessage()})
+                                                                    'error': failure_.getErrorMessage()})
 
     def findServiceEntities(self, category, type_, jid_=None, profile_key=C.PROF_KEY_NONE):
         """Return all available items of an entity which correspond to (category, type_)