diff --git a/apps/dsm/mods/mod_conference/ModConference.cpp b/apps/dsm/mods/mod_conference/ModConference.cpp
index 7b9ac625..bb23ca84 100644
--- a/apps/dsm/mods/mod_conference/ModConference.cpp
+++ b/apps/dsm/mods/mod_conference/ModConference.cpp
@@ -65,10 +65,12 @@ EXEC_ACTION_START(ConfPostEventAction) {
   unsigned int ev;
   if (str2i(ev_id, ev)) {
     ERROR("decoding conference event id '%s'\n", ev_id.c_str());
+    sc_sess->SET_RES(DSM_RES_UNKNOWN_ARG);
     return false;
   }
 
   AmConferenceStatus::postConferenceEvent(channel_id, ev, sess->getLocalTag());
+  sc_sess->SET_RES(DSM_RES_OK);
 } EXEC_ACTION_END;
 
 static bool ConferenceJoinChannel(DSMConfChannel** dsm_chan, 
@@ -94,6 +96,7 @@ static bool ConferenceJoinChannel(DSMConfChannel** dsm_chan,
 							     sess->getLocalTag());
   if (NULL == chan) {
     ERROR("obtaining conference channel\n");
+    throw DSMException("conference");
     return false;
   }
   if (NULL != *dsm_chan) {
@@ -130,9 +133,9 @@ EXEC_ACTION_START(ConfJoinAction) {
       // add to garbage collector
       sc_sess->transferOwnership(dsm_chan);
 
-      sc_sess->SET_ERRNO(DSM_ERRNO_OK);
+      sc_sess->SET_RES(DSM_RES_OK);
   } else {
-    sc_sess->SET_ERRNO(DSM_ERRNO_UNKNOWN_ARG);
+    sc_sess->SET_RES(DSM_RES_UNKNOWN_ARG);
   }
 } EXEC_ACTION_END;
 
@@ -160,10 +163,12 @@ EXEC_ACTION_START(ConfLeaveAction) {
   DSMConfChannel* chan = getDSMConfChannel(sc_sess);
   if (NULL == chan) {
     WARN("app error: trying to leave conference, but channel not found\n");
-    sc_sess->SET_ERRNO(DSM_ERRNO_UNKNOWN_ARG);
+    sc_sess->SET_RES(DSM_RES_UNKNOWN_ARG);
     return false;
   }
   chan->release();
+
+  sc_sess->SET_RES(DSM_RES_OK);
 } EXEC_ACTION_END;
 
 CONST_ACTION_2P(ConfRejoinAction, ',', true);
@@ -179,9 +184,9 @@ EXEC_ACTION_START(ConfRejoinAction) {
   }
 
   if (ConferenceJoinChannel(&chan, sess, sc_sess, channel_id, mode)) {
-      sc_sess->SET_ERRNO(DSM_ERRNO_OK);
+      sc_sess->SET_RES(DSM_RES_OK);
   } else {
-    sc_sess->SET_ERRNO(DSM_ERRNO_UNKNOWN_ARG);
+    sc_sess->SET_RES(DSM_RES_UNKNOWN_ARG);
   }
 } EXEC_ACTION_END;
 
@@ -193,4 +198,5 @@ EXEC_ACTION_START(ConfSetPlayoutTypeAction) {
     sess->rtp_str.setPlayoutType(JB_PLAYOUT);
   else 
     sess->rtp_str.setPlayoutType(SIMPLE_PLAYOUT);
+  sc_sess->SET_RES(DSM_RES_OK);
 } EXEC_ACTION_END;
diff --git a/apps/dsm/mods/mod_conference/Readme.mod_conference.txt b/apps/dsm/mods/mod_conference/Readme.mod_conference.txt
index f9edb3bc..8b70820a 100644
--- a/apps/dsm/mods/mod_conference/Readme.mod_conference.txt
+++ b/apps/dsm/mods/mod_conference/Readme.mod_conference.txt
@@ -1,12 +1,14 @@
 Actions: 
  conference.join(string roomname [, string mode])
    mode = "" | speakonly | listenonly
+   Throws "conference" Exception if conference can not be joined (currently never).
 
  conference.leave()
    destroy conference channel. Close playlist first!!!!!
 
  conference.rejoin(string roomname [, string mode])
    mode = "" | speakonly | listenonly
+   Throws "conference" Exception if conference can not be joined (currently never).
 
  conference.postEvent(string roomname, int event_id)