> Such a mirroring might be perceived by them as rude, though.

Yes, and therefore, I would just drop them a note, explaining your
problem (trying to create a source-based package of their software), and
pointing out why this "click to accept" is not really appropriate for
GPL licensed software.  

You might even point to this:
http://www.onlamp.com/pub/a/onlamp/2005/03/31/packaging.html
http://www.onlamp.com/pub/a/onlamp/2005/04/28/packaging2.html

GH

-- 
:wq