Page processing/display anomaly

I have a common header for all the pages on my site. This header has a link with the following code: javascript:popUp550_450('http://www.website.com/page.php?referingpage=<?php echo ($_SERVER['SERVER_NAME']); echo ($_SERVER['PHP_SELF']); ?>') This code works exactly right on all pages of the site except one. On the page answer.php, it doesn't evalutate the php code in the above (so the link literally is just as shown above and the javascript won't even call for a pop-up window). answer.php usually has some get variables attached, like so: answer.php?showanswer=dog but even when I type in exactly answer.php with no variables added, the php portion of the link won't evaluate/work. Does anyone have any idea as to why? It's a php page, shouldn't it evaluate? Allan Cleaveland Webmaster and Computer Technician Math Department Univeristy of Arkansas