HTTP POST ISSUE

I've got two versions of a page with registration forms where the info submitted in the form on the previous page is supposed to be pre-filled in, but it only works on one of the forms even though both have the same code: <div class="input"><input type="text" name="email" id="emailid" value="" size="30" /> Will send URL's on request. This should be a super-simple job for a PHP programmer.