WCF service exposed for AJAX client doesn't generate JavaScript proxy class

I wrote a simple WCF service class exposed for AJAX client calling. The details for the code and web.config can be seen below. It works perfectly fine in my VS 2008 development station, but when deployed, the JavaScript code that calls Service.EndSession() bombs,  complaining the 'Service' is undefined!!! From the VS IDE itself (when I choose to debug IE error), "js" doesn't show up in the list of "Script Documents" which usually lists all dynamically generated JS files (AJAX & ASP .NET). Please help....
CODE:
<ServiceContract([Namespace]:="", Name:="Service")> ...