PHP loads extension(dynamic module) in parsing php3.ini.
  ; by calling php3_config_ini_startup

And then call module_startup_modules() funtion.

But module_startup_modules reset module_count to 0;

So entension module number is conflicts to the module_number of  dynamic module loaded by dl() php function.

This is critical in resource deallocation.
Because it try to deallocate extention module resource after request processing.