Yes, i tried using both the allheader tuple as well as the header, alone. Using header infact did change the arg structure's referer, but the document.referrer still was'nt bein rewritten. Same with the arg_rewrite method. The Arg was definitely being edited, without forcing a change in the document.referer.
I suppose the only explanation is that the browser itself sets the request referrer , and thus overriding any manipulation headers. : /