Index: lams_tool_chat/src/java/org/lamsfoundation/lams/tool/chat/web/actions/LearningWebsocketServer.java
===================================================================
diff -u -rab2b6923490ce38dc647ea66d6768966fbc40cfd -rf9f746312dac96f91730b91bb3023f8823502a3d
--- lams_tool_chat/src/java/org/lamsfoundation/lams/tool/chat/web/actions/LearningWebsocketServer.java	(.../LearningWebsocketServer.java)	(revision ab2b6923490ce38dc647ea66d6768966fbc40cfd)
+++ lams_tool_chat/src/java/org/lamsfoundation/lams/tool/chat/web/actions/LearningWebsocketServer.java	(.../LearningWebsocketServer.java)	(revision f9f746312dac96f91730b91bb3023f8823502a3d)
@@ -99,13 +99,14 @@
 			    if (sessionWebsockets.isEmpty()) {
 				entryIterator.remove();
 				LearningWebsocketServer.rosters.remove(toolSessionId);
+				lastSendTimes.remove(toolSessionId);
 			    }
 			}
 		    }
 
 		    Thread.sleep(SendWorker.CHECK_INTERVAL);
 		} catch (InterruptedException e) {
-		    LearningWebsocketServer.log.warn("Stopping Chat worker thread");
+		    LearningWebsocketServer.log.warn("Interrupted Chat worker thread");
 		    stopFlag = true;
 		} catch (Exception e) {
 		    // error caught, but carry on