Description:
------------
I use php as an ISAPI server extension on my self-written web server. Works quite well, except when I remove the extension from memory, i.e., FreeLibrary(hInst) where hInst is the handle to php4isapi.dll. In most cases, this causes the DLL to go belly-up.

I traced the problem into the Zend stuff - in zend_shutdown() there's a call to zend_shutdown_timeout_thread() which terminates the timeut thread... or at least it's supposed to do so. Unfortunately, zend_shutdown_timeout_thread() just posts a WM_QUIT message for the thread and then happily goes on deleting thread data... and when the timeout thread finally processes the WM_QUIT message, all data are gone, and it hops to an unused address.

Solution to this problem is simple - just make sure that zend_shutdown_timeout_thread() allows the other thread to receive the WM_QUIT message before continuing. I've included a modified version in the "reproduce code" area below which has the desired effect.

Reproduce code:
---------------
void zend_shutdown_timeout_thread()
{
	if (!timeout_thread_initialized) {
		return;
	}
	PostThreadMessage(timeout_thread_id, WM_QUIT, 0, 0);
	Sleep(0);  // <- this does the trick!
}