zend_register_list_destructors_ex problem

I'm trying to create my own resource for a project I'm working on. I seem to be having problems using zend_register_list_destructors_ex that I'm having a hard time figuring out. When I stick in the code, recompile my extension, and the run the script it works the first few times. After 2 or 3 runs it starts displaying "Fatal error: Nesting level too deep - recursive dependency? in Unknown on line 0" If I comment the zend_register_list_destructors_ex line out and recompile it'll work fine no matter how many times I run it Here's my code that resides in my PHP_MINIT_FUNCTION- le_restype = zend_register_list_destructors_ex(free_res, NULL, "My Resource Object", module_number); Does anyone have any insight on why this may be happening? Thanks all Sean