Index: lams_tool_nb/src/java/org/lamsfoundation/lams/tool/noticeboard/util/NbAuthoringUtil.java
===================================================================
diff -u -ra766c8fe51dfa314947b20ef98e525d63b328fbe -r24d83fff08a23322463b95ba0f194047243eeee3
--- lams_tool_nb/src/java/org/lamsfoundation/lams/tool/noticeboard/util/NbAuthoringUtil.java	(.../NbAuthoringUtil.java)	(revision a766c8fe51dfa314947b20ef98e525d63b328fbe)
+++ lams_tool_nb/src/java/org/lamsfoundation/lams/tool/noticeboard/util/NbAuthoringUtil.java	(.../NbAuthoringUtil.java)	(revision 24d83fff08a23322463b95ba0f194047243eeee3)
@@ -20,6 +20,9 @@
  */
 package org.lamsfoundation.lams.tool.noticeboard.util;
 
+import javax.servlet.http.HttpServletRequest;
+import org.lamsfoundation.lams.tool.noticeboard.NoticeboardConstants;
+
 /**
  * @author mtruong
  *
@@ -40,4 +43,13 @@
 	 		Long contentId = new Long(Long.parseLong(toolContentId));
 	 		return contentId;
 	 	}
+	 	
+	 
+	 	public static void cleanSession(HttpServletRequest request)
+	 	{
+	 	    request.getSession().removeAttribute(NoticeboardConstants.TOOL_CONTENT_ID);
+	 	    request.getSession().removeAttribute(NoticeboardConstants.RICH_TEXT_CONTENT);
+	 	    request.getSession().removeAttribute(NoticeboardConstants.RICH_TEXT_OFFLINE_INSTRN);
+	 	    request.getSession().removeAttribute(NoticeboardConstants.RICH_TEXT_ONLINE_INSTRN);
+	 	}
 }