How free is free?

["Jaldhar H. Vyas" <jaldhar@braincells.com>]

I have been reading the various messages on when software is to
be considered free.  I've also just read the licensing terms for lprng
which say:

...is  distributed under  the  GNU  Copyleft  License...

but then go on to say:

..The  Artisitic  license meets the needs of most end users; a com-
mercial license and support is available for users  and institutions 
that  require it...

Yet this is considered acceptable for Debian.  Whereas qt is free for the
development of free software and the source is distributable under the X
windows system (which could well exist on non-unix platforms) and yet is
considered non-free.  How come?

-- Jaldhar