Few thunderbird questions

[Steel City Phantom]

ok, bsd 6, kde 3.5, thunderbird 1.5, firefox 1.5

few things that are slightly annoying in thunderbird that if someone 
knows how to fix, i would be very happy.

1) when i click on a url link in thunderbird, nothing happens.  how to i 
have it open firefox and go to that url
2) when mail arrives, it does a system beep.  is there any way to map 
that to a KDE event so i can put some kind of meaningful sound to it?


thanks