Ahh. Yes, I missed that. I think the GPL specifically answers this
question:
http://www.fsf.org/copyleft/gpl.html
"Finally, any free program is threatened constantly by
software patents.
We wish to avoid the danger that redistributors of a free
program will
individually obtain patent licenses, in effect making the program
proprietary. To prevent this, we have made it clear that
any patent must
be licensed for everyone's free use or not licensed at all."
Sender-ID is licensed for everyone's free use and it is not
necessary for individual users or distributors of the program
to obtain independent licenses.
It is very clear to me that the SenderID license is not a
genuine impediment here. The impediments are being created by
people who want to see them.