absolute URLS Can work.
another method would be to use an htaccess file and mod rewrite:
or you could use the following php code at line 1 of the pages that should be access using ssl:
<?php if((!(isset($_SERVER['HTTPS']))) || ($_SERVER['HTTPS'] == "") || ($_SERVER['HTTPS'] == "off"))header("Location: https://" . $_SERVER['HTTP_HOST'] . $_SERVER['PHP_SELF']); ?>