[LoadUIWeb] Cookies and Javascript for WebLoadUI Test

I have an application that adds a cookie variable using javascript.  The javascript function that does this is executed in a callback from a button click.  



When we play the scenario, the javascript is not getting executed, so the cookie variable is not being added.  This is causing a server side error in a page later on in the test.



Is there a way we can execute a javascript after a request is sent during playback?  If not, is there a way we can add the cookie variable after a request without using javascript?



Thanks,

Richard