Calling web service in Dynamic extender from java script doesn't work in Master page using file

Hi,
Please help me with this..
I have a user controller which uses a dynamic extender and call a web service.When i use it in ASPX page independent of master apge it works fine.
But when I drop this controller in to a page using master page.It does not work.I debug the JS(I call JS function from event triggering) and it goes particular place and up to place where invoking the service.But Service is not invoked from Java script like it should be.Worst par tis NO EXCEPTION IS THROWN..
Please provide me a solution for this? ...