I have implemented 0355 and 0356 Xeps for ejabberd and used Sat to check it's validation (You can find it on https://github.com/Amuhar/ejabberd/tree/xep0356). All things work Ok, but I can't subscribe to users (with Prosody I can do it): 2016-07-31T12:47:42+0300 [XmlStream,client] subscription request from [libervia@localhost] 2016-07-31T12:47:42+0300 [XmlStream,client] Unhandled Error Traceback (most recent call last): File "/build/buildd/python2.7-2.7.6/Modules/pyexpat.c", line 618, in EndElement File "/usr/local/lib/python2.7/dist-packages/twisted/words/xish/domish.py", line 797, in _onEndElement self.ElementEvent(self.currElem) File "/usr/local/lib/python2.7/dist-packages/twisted/words/xish/xmlstream.py", line 107, in onElement self.dispatch(element) File "/usr/local/lib/python2.7/dist-packages/twisted/words/xish/utility.py", line 317, in dispatch callbacklist.callback(obj) --- <exception caught here> --- File "/usr/local/lib/python2.7/dist-packages/twisted/words/xish/utility.py", line 107, in callback methodwrapper(*args, **kwargs) File "/usr/local/lib/python2.7/dist-packages/twisted/words/xish/utility.py", line 27, in __call__ self.method(*nargs, **nkwargs) File "/usr/local/lib/python2.7/dist-packages/wokkel/xmppim.py", line 87, in _onPresence handler(presence) File "/usr/local/lib/python2.7/dist-packages/wokkel/xmppim.py", line 119, in _onPresenceSubscribe self.subscribeReceived(JID(presence["from"])) File "/usr/local/lib/python2.7/dist-packages/sat/core/xmpp.py", line 460, in subscribeReceived item = self.parent.roster.getItem(entity) File "/usr/local/lib/python2.7/dist-packages/sat/core/xmpp.py", line 306, in getItem return self._jids.get(entity_jid, None) exceptions.AttributeError: 'NoneType' object has no attribute 'get' Details: SàT version: 0.6.0D Libervia version: 0.6.0D OS: Distributor ID: LinuxMint Description: Linux Mint 17.3 Rosa Release: 17.3 Codename: rosa