The only way to setup ICS, XP and ZoneAlarm (ZA) is to download and then purchase ZoneAlarm Pro 3.x
It has a wizard that will configure XP ICS and ZA to work together. I had similiar issues with my home network and the pro version corrected the issue. I do not know of or think that there is a way to otherwise bypass it w/o pro version 3.x.
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