CMS Pro iframe PHP Sessions bug fix

I bought a CMS application here: [login to view URL] and its very well written although i need to add one little thing. i have a 'post' in the CMS which has an iframe (doesnt accept php in content directly), problem is, in Chrome and Firefox (IE works fine) the PHP session seems to change or get lost in the iframe. The same thing occurs with a javascript popup of my external php file. All i need to do is get the currently logged in username in my iframe page. The CMS author gave me this to get the username from the session: define("_VALID_PHP", true); require_once("[login to view URL]"); print $user->username; This works fine in IE but in chrome or firefox is prints 'Guest' instead as the session id has changed. I attempted to google fix this problem and found no solution yet so looking for someone to help resolve this issue for me.