diff --git a/src/tmp/wokkel/rsm.py b/src/tmp/wokkel/rsm.py
index 61d9b80d..a989b465 100644
--- a/src/tmp/wokkel/rsm.py
+++ b/src/tmp/wokkel/rsm.py
@@ -194,7 +194,7 @@ class RSMResponse():
         try:
             set_elt = element.elements(NS_RSM, 'set').next()
         except StopIteration:
-            return RSMNotFoundError()
+            raise RSMNotFoundError()
 
         response = RSMResponse()
         for elt in list(set_elt.elements()):
@@ -331,9 +331,12 @@ class PubSubClient(pubsub.PubSubClient):
                     items.append(element)
 
             if request.rsm:
-                response = RSMResponse.parse(iq.pubsub)
-                if response is not None:
-                    self._rsm_responses[ext_data['id']] = response
+                try:
+                    response = RSMResponse.parse(iq.pubsub)
+                    if response is not None:
+                        self._rsm_responses[ext_data['id']] = response
+                except RSMNotFoundError:  # target pubsub server doesn't support RSM
+                    pass
             return items
 
         d = request.send(self.xmlstream)