what context do i need to transfer control to a jsp ??

in my jboss.xml i have

<jboss-web>
 <context-root>/webDir</context-root>
</jboss-web>

and a .jsp called welcome.jsp in the root dir of my .war

i have the following snipet of code in my servlet

 RequestDispatcher dispatcher =
 request.getRequestDispatcher("/webDir/welcome.jsp");
 dispatcher.forward(request,response);

and the following message is returned by Jboss 3.2.3

"The requested resource (/webDir/welcome.jsp) is not available."

but when i change the path to

 RequestDispatcher dispatcher
 = request.getRequestDispatcher("webDir/welcome.jsp");

i get

"The requested resource (/servlet/webDir/welcome.jsp) is not available".

What can i do to rectify this