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MSN for mac doesn't do video at the moment.


Adium, and

aMSN is a free open source MSN Messenger clone, with features such as:

Offline Messaging
Voice Clips
Display pictures
Custom emoticons
Multi-language support (around 40 languages currently supported)
Webcam support
Sign in to more than one account at once
Full-speed File transfers
Group support
Normal, and animated emoticons with sounds
Chat logs
Timestamping
Event alarms
Conferencing support
Tabbed chat windows
 
I highly doubt Adium supports video-chat.

Did you try aMSN? Or you could just ask them to use Skype?
 
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