I'm writing a custom module for a large project, and currently implementing SimpleTests for my code. setUp() is loading 17 modules to run the tests. Five of the modules require autoload. When my module attempts to use it's class the following error is thrown: Class 'CustomClass' not found - PHP Fatal error - custom.module (class/module name changed).

If I add autoload_registry_rebuild(); directly after the call to setUp(), then everything works as expected. Problem seems similar to #818714: Autoload fails to find classes in simpletest, but that issue should be fixed.