On Tue, 7 Oct 2008, Mike Miller wrote:

> With version 0.12 (5 Jan 1991), Torvalds switched his license to the GPL:
>
> http://www.kernel.org/pub/linux/kernel/Historic/old-versions/RELNOTES-0.12

That should have said "16 Jan 1992".  I forgot to finish checking the 
dates before I sent it.  I know the "5 Jan 1991" date is wrong.  I got the 
other date here...

http://ftp.cdut.edu.cn/pub2/linux/kernel/history/Master.html

...but I don't know that those dates are right either.  Unfortunately, 
Linus didn't date all of his early release notes.

Mike