cocoaforge

Thanks for the tip! Working fine.

So… It's not working with the svn version.
The only thing I can find about the proxy is that it is "Application and Content Networking System Software 5.4.1", by Cisco.
Edit: Anyway, I guess this is a problem with libpurple.

I'm having a similar problem, with a Cisco proxy at work. I'll have a look monday which type it is and try the latest svn version.
Meanwhile, Live Messenger in VMWare connects just fine.