Index: SPARQLBuilderWWW/src/java/org/biohackathon/SPARQLBuilder/www/PLServlet.java
===================================================================
--- SPARQLBuilderWWW/src/java/org/biohackathon/SPARQLBuilder/www/PLServlet.java (revision 171)
+++ SPARQLBuilderWWW/src/java/org/biohackathon/SPARQLBuilder/www/PLServlet.java (revision 175)
@@ -71,9 +71,10 @@
         String en = request.getParameter("endclass");
         
-        //HttpSession session = request.getSession();
-        //QueryPathGenerator qpg = (QueryPathGenerator)session.getAttribute("qpg");
-        //if ( qpg == null ){
-           QueryPathGenerator qpg = new QueryPathGenerator(ep);
-        //}
+        HttpSession session = request.getSession();
+        QueryPathGenerator qpg = (QueryPathGenerator)session.getAttribute("qpg");
+        if ( qpg == null ){
+        //QueryPathGenerator 
+                qpg = new QueryPathGenerator(ep);
+        }
         SClass[] classes = qpg.getClasses(null);
         Path[] paths = qpg.getPaths(st, en, true);
Index: SPARQLBuilderWWW/src/java/org/biohackathon/SPARQLBuilder/www/CLServlet.java
===================================================================
--- SPARQLBuilderWWW/src/java/org/biohackathon/SPARQLBuilder/www/CLServlet.java (revision 162)
+++ SPARQLBuilderWWW/src/java/org/biohackathon/SPARQLBuilder/www/CLServlet.java (revision 175)
@@ -70,9 +70,10 @@
 	PrintWriter out = response.getWriter();
         String ep = request.getParameter("ep");
-        //HttpSession session = request.getSession();
-        //QueryPathGenerator qpg = (QueryPathGenerator)session.getAttribute("qpg");
-        //if ( qpg == null ){
-           QueryPathGenerator qpg = new QueryPathGenerator();
-        //}
+        HttpSession session = request.getSession();
+        QueryPathGenerator qpg = (QueryPathGenerator)session.getAttribute("qpg");
+        if ( qpg == null ){
+        //QueryPathGenerator 
+                   qpg = new QueryPathGenerator();
+        }
         qpg.setSPARQLendpoint(ep);
         SClass[] classes = qpg.getClasses(null);
Index: SPARQLBuilderWWW/src/java/org/biohackathon/SPARQLBuilder/www/EPServlet.java
===================================================================
--- SPARQLBuilderWWW/src/java/org/biohackathon/SPARQLBuilder/www/EPServlet.java (revision 162)
+++ SPARQLBuilderWWW/src/java/org/biohackathon/SPARQLBuilder/www/EPServlet.java (revision 175)
@@ -84,6 +84,6 @@
         JsonArray ja = jab.build();
 	out.print(ja);
-        //HttpSession session = request.getSession();
-        //session.setAttribute("qpg", qpg);
+        HttpSession session = request.getSession();
+        session.setAttribute("qpg", qpg);
     }