Can anyone jog my memory on HTTP_REFERER & Javascript "location:replace"?

Hi! I had found a way around the problem and it work, but when I enabled the web security features, it messed up. So, with some debugging and I found the problem and I'm not sure how to find a way around it. You see .... I use page1.php to do certain features but the problem is that PHP execution get done before the file (non-PHP programming) in passthru('...') get done later. So, I can't get the result before PHP finish executing. There, I came up with the Javascript where the non-PHP scripting can spit out the Javascript code and the Javascript take care of it. It work so well. To my dismay, the PHP pick up the HTTP_REFERER doesn't work because HTTP_REFERER was all blank when Javascript use "location.replace('');" code. So, it messed up the webpage. Is there a way to get the HTTP_REFERER code? Or a different Javascript code? I mean there's no way to get the PHP execution to pause while the non-PHP programming get done first. Is there? Thanks, Scott