I just added
"http://download.eclipse.org/technology/babel/update-site/ganymede"; to the
"Software Updates and Add-ons" dialog in my Eclipse SDK 3.4.2. After about
a minute or two (since Babel has MANY language packs), the complete list
of language packs in all languages is displayed.
Maybe you have a slower connection and the operation timed out? Try to
wait for a longer time to see if that's better.