To my embaressment, I've found that if you set the Internet settings of
ZoneAlarm to "medium", and give netrek full privileges, a netrek client
works fine after all.

I've heard a couple of other players agree with me that ZoneAlarm caused
them problems with netrek, so it might be a good idea anyway to add a
subsection about ZoneAlarm (and any other off-the-download "firewall"
products) to the relevant client documents/FAQs.

-Dan / Charity