Index: JetspeedEngine.java
===================================================================
--- JetspeedEngine.java
+++ JetspeedEngine.java
@@ -176,9 +176,10 @@
     public void service( RequestContext context ) throws JetspeedException
     {        
         long start = System.currentTimeMillis();
-        String targetPipeline = context
+        String targetPipeline = null;
+        String requestPipeline = context
                 .getRequestParameter(PortalReservedParameters.PIPELINE);
-        if (null == targetPipeline)
+        if (null == requestPipeline)
         {
             targetPipeline = (String)context.getAttribute(PortalReservedParameters.PIPELINE);                
             if (null == targetPipeline)
@@ -197,6 +198,10 @@
                     targetPipeline = this.defaultPipelineName;
                 }
             }
+        } else {
+        	if (pipelineMapper.containsValue(requestPipeline)) {
+        		targetPipeline = requestPipeline;
+        	}
         }
         Pipeline pipeline = null;
         if (targetPipeline != null)