var orginalFormAction = null;

//capture the current form action value
function BeginRequestHandler() {
  orginalFormAction = theForm.action;
}

//set the form action value back to the
//correct value
function EndRequestHandler() {
  theForm.action = orginalFormAction;
  theForm._initialAction = orginalFormAction;
}

function RegisterRequestHandlers() {

  if (typeof (Sys) != "undefined") {

    Sys.WebForms.PageRequestManager.getInstance().add_endRequest(EndRequestHandler);
    Sys.WebForms.PageRequestManager.getInstance().add_beginRequest(BeginRequestHandler);
    Sys.Application.notifyScriptLoaded();

  }
}

//register request handlers after the application 
//has successfully loaded.
Sys.Application.add_load(RegisterRequestHandlers);