On 9/22/07, Luke -Jr <luke@dashjr.org> wrote:

> > a free download, called "Microsoft Services for Unix"

The GPL doesn't force automatic upgrades. If Microsoft started using it under
GPLv2, nobody can stop them from continuing to use it under GPLv2.

If they're using GPL software (which isn't also offered under some other license), then they have to distribute it, and any works derived therefrom, under a GPL-compatible license (one which gives downstream all the rights the GPL requires). I don't believe that Microsoft distributes GPL software (because I don't buy the idea that selling coupons redeemable at Novell constitutes 'distribution' any more than giving McDonald's gift certificates to my daughter would make me a restaurant).

However, as Linus has pointed out, anyone using software that is licensed under "GPLv2" (as opposed to "GPLv2+") is required by the terms of the license to distribute it downstream under GPLv2 or a compatible license. GPLv3 is NOT compatible with GPLv2 because it imposes additional restrictions upon those downstream users. Only in the case where the changes are deeded back to the upstream maintainer can the license be changed to GPLv3.