Effective ipfw rules for blocking MSN Messenger ... ?

[Marc G. Fournier]

I just setup a FreeBSD box for a router, so that I could make use of ipfw 
to block MSN Messenger traffic ... but I'm having a bugger of a time 
finding a "definitive" list of what needs to be blocked :(

MSN Messenger appears to be smart enough to go *around* the usual port 
1863 and onto port 80 if it needs to ...

Can someone that has successfully done this using ipfw send me a list of 
rules, since obviously I'm not catching it :(

Thanks ...

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Marc G. Fournier           Hub.Org Networking Services (http://www.hub.org)
Email: scrappy at hub.org           Yahoo!: yscrappy              ICQ: 7615664