How to add a query string value to pass to servers in teh pool?

Thanks for the follow up, but this still does not seem to function as I would expect. Basically everything works accept it I never see and actual & logged. So for the example above if the entered URL were "http://www.foo.com/bar" It is changed to "http://www.foo.com/bar?p1=v1" just fine. However if the URL is "http://www.foo.com/bar?a=b" I get this in the logs. "http://www.foo.bar?a=bp1=v1". Notice the missing & in the second example. I tried eascabing the & with a backslash, but no luck.