[Zope] Zope crash - Microsoft URL Control

Hi, My Zope server 2.5.1 (Win32) was crashed and was 3 days out after receive following hit: 192.168.1.200 - Anonymous [31/Dec/2002:06:42:56 +0200] "GET / HTTP/1.1" 200 1584 "" "Microsoft URL Control - 6.00.8169" (IP address is from our POUND proxy) Microsoft URL Control is known as something about spam agent/worm/virus for FormMail.pl (as say googled search). I dont know exactly time whem my zope fails, but after that log message was nothing until I was restart Zope service. It is security issue or it is another reason? Many thanks, J. Lukesh