Segmentation fault / Error 324 (net::ERR_EMPTY_RESPONSE) on enable Rules

This seems like the same issue reported in #1258284: Can't edit rules due to internal server error since 7.x-2.0-rc1 but that issue was supposedly resolved several releases ago. When I enable either rules 7.x-2.1 or the current 7.x-2.x-dev I immediately get a Segmentation Fault in drush and a Error 324 (net::ERR_EMPTY_RESPONSE) in admin/modules. This site's been running for over a year in this environment with many contrib modules active without any similar problems.

PHP Version => 5.2.17
MySQL Client API version => 5.0.95
Server version: Apache/2.2.17 (Unix)