Thread:Project:Support desk/Error on Special:SpecialPages

I've just upgraded to 1.22.0. Most things seem to be working but I can't display Special:SpecialPages. Looking in the error log I get a seg fault the first time I try after restarting Apache. Thereafter every attempt results in the message "zend_mm_heap corrupted". I'm running PHP 5.3.6 with MySQL 5.1.56 and APC 3.1.6. I have a long list of extensions installed. As they haven't been tagged for 1.22 yet I'm using the head version for all those that weren't bundled with MediaWiki. Any ideas?