Services crashes my Apache

I'm testing the Services API and modules with a view to using them in production - testing server is Windows XP running WAMP. When I attempt to administer the The XMLRPC Server ( XMLRPC - /services/xmlrpc ) from within Drupal something is causing Apache to crash. - "Apache has
encountered a problem and needs to close".

Error signature:-
szAppName : httpd.exe szAppVer : 2.2.4.0 szModName : php5ts.dll
szModVer : 5.2.1.1 offset : 00179f9a

Apache Log:-

[Wed Mar 14 11:57:13 2007] [notice] Parent: child process exited with status 3221225477 -- Restarting.
[Wed Mar 14 11:57:14 2007] [notice] Apache/2.2.4 (Win32) PHP/5.2.1 configured -- resuming normal operations
[Wed Mar 14 11:57:14 2007] [notice] Server built: Jan  9 2007 23:17:20
[Wed Mar 14 11:57:14 2007] [notice] Parent: Created child process 440
[Wed Mar 14 11:57:14 2007] [notice] Child 440: Child process is running
[Wed Mar 14 11:57:14 2007] [notice] Child 440: Acquired the start mutex.
[Wed Mar 14 11:57:14 2007] [notice] Child 440: Starting 250 worker threads.
[Wed Mar 14 11:57:14 2007] [notice] Child 440: Starting thread to listen on port 80.

I'm not sure where the root of the problem is, is it Windows? I assume its something to do with php5 module in apache, I know that WAMP is off topic but... Any suggestions?