Symptom: In the admin area, when accessing pages that have pulldown menus on them, you might occasionally see a "catchable fatal error in html_output.php".
Happens only in PHP5

Cause: leftover legacy code incompatible with PHP5

Solution: Interim workaround is available by using the patched files posted here:
http://www.zen-cart.com/forum/showpo...0&postcount=10