From: "Gregory Brown" <gregory.t.brown / gmail.com>
>
> The trouble is that the Ruby License (on its own) is not considered a
> free software license by the FSF, which makes it incompatible with the
> GPL.
> The only thing that makes Ruby free software in the eyes of the FSF is
> the fact that it is dual licensed.

I tried to locate some information regarding the FSF
not considering the Ruby License a free software 
license, but all I've found so far was this:

http://www.gnu.org/licenses/license-list.html#Ruby

Which says: 

   License of Ruby

   This is a free software license ...


?

Regards,

Bill