I'm getting that "Site error: the file /usr/local/cpanel/whostmgr/docroot/themes/x/mon.php requires the ionCube PHP Loader ioncube_loader_lin_4.4.so to be installed by the site administrator." message everytime I try to use WHMXtra. The problem, however, is that I just installed the 64-bit ioncube (it's listed under my phpinfo), so I'm not sure why this is happening.

Does anyone know what to do?

Nevermind, I figured it out.

can you remeber how you figured this out?

same problem here. WHMXTRA is not wprking because of ioncube installed on php.ini