When you use eaccelerator 0.9.5 or eaccelerator-svn301 with a php 5.2.1 working as httpd module it causes huge cpu overload (like 100%*120 = 12000%) over time. For me it happened like every 60 minutes on one server and on another it didnt happened yet (server wasnt on much php usage). Other ppl on internet said that it happens like every 10 hours so it probably depends on usage on php... In httpd log there is:
zend_mm_heap corrupted
zend_mm_heap corrupted
zend_mm_heap corrupted
This only happens with php 5.2.1. Its not happening with 5.2.0. I'm just reporting that stuff thats all.