So it wasn't just me then! .... mullit.. which mac are you using. I had the unexpected quit problem with 4.10.0, .. but I realize now I did hardly any downloading with it, and as I recall didn't actually complete a file! so I really don't know if I would have had the same sypmptyms as you regarding downloads, and iTunes. I have at the moment reverted to an older version, but I am about to try something else which I will let you know about when I know the results!
This was the thread about my problem .. if you ignore the private jokes and general social bits LOL
http://www.gnutellaforums.com/showth...=&pagenumber=1
I think others will look into this as well .. and as I said a few more details about your computer and also your java version would be helpful.
My specs:- MacG3 400Mhx Blue and White OSX 4.3.9 Java I.4.2_09 Memory 320MB