Php – Apache segfaults on WordPress admin page

I can access the frontend of a new WordPress setup without issue. I can also log in with a user account without issue. However, if I try to log in with an admin account I get a 500 error about 70-80% of the time.

If I do manage to get through to the WP dashboard, any page within the admin panel will cause the error only /sometimes/ – I can't find a set way to reproduce the error.

Apache's error log shows a segmentation fault for each of these 500 errors.

I started my investigation with WordPress:

• Disabled all WP plugins
• Reset the theme to default
• Removed .htaccess and hit the php pages directly

The error sill intermittently occured.

I figured my next step should be to get a core dump of the Apache thread that died to see if there are any clues, but I can't get it to dump.

I'm running Debian 6.0.4 and have followed the instructions in /usr/share/doc/apache2.2-common/README.backtrace, which state:

1) Install the packages apache2-dbg libapr1-dbg libaprutil1-dbg gdb.

2) Add "CoreDumpDirectory /var/cache/apache2" to your apache
configuration.

3) Execute as root:
/etc/init.d/apache2 stop
ulimit -c unlimited
/etc/init.d/apache2 start

4) Do whatever it takes to reproduce the crash. There should now be
the file /var/cache/apache2/core .

Still, the core files aren't being dumped, and Apache's error log doesn't have (core dumped) in the segmentation fault lines.

Any ideas?