i don't know. i agree that it should be GPLd, a lot of companies make money from GPL software, but macintosh users seem a lot more predisposed to using software from proprietary sources if it's good software, in fact they are sometimes quite verbal about how they prefer their good quality proprietary software over any GPLd 'rubbish' that you can get any old where. but then other people might remark casually that that's just sour grapes on the part of somebody who needs to justify $6000 spent on proprietary software...
still, may i point out that while macmessenger is proprietary it appears to be FREE, and he is only asking for donations, not charging for the software. so in my opinion ethically, this is a lot better than most proprietary setups. also, with this setup, there is only benefit to be had from GPLing the software.
[ April 23, 2003: Message edited by: Calum: crusader for peace & freedom ]