--- a/sat/plugins/plugin_xep_0045.py	Fri Jan 25 09:06:29 2019 +0100
+++ b/sat/plugins/plugin_xep_0045.py	Sat Jan 26 20:07:45 2019 +0100
@@ -1133,6 +1133,24 @@
                 u"received history in unexpected state in room {room} (state: "
                 u"{state})").format(room = room.roomJID.userhost(),
                                     state = room.state))
+            if not hasattr(room, "_history_d"):
+                # XXX: this hack is due to buggy behaviour seen in the wild because of the
+                #      "mod_delay" prosody module being activated. This module add an
+                #      unexpected <delay> elements which break our workflow.
+                log.warning(_(u"storing the unexpected message anyway, to avoid loss"))
+                # we have to restore URI which are stripped by wokkel parsing
+                for c in message.element.children:
+                    if c.uri is None:
+                        c.uri = C.NS_CLIENT
+                mess_data = self.client.messageProt.parseMessage(message.element)
+                message.element._mess_data = mess_data
+                self._addToHistory(None, user, message)
+                if mess_data[u'message'] or mess_data[u'subject']:
+                    self.host.bridge.messageNew(
+                        *self.client.messageGetBridgeArgs(mess_data),
+                        profile=self.client.profile
+                    )
+                return
         room._history_d.addCallback(self._addToHistory, user, message)
         room._history_d.addErrback(self._addToHistoryEb)