The SVN repository for the Linux drum machine software, Hydrogen has recently moved. You can read today's hydrogen-devel post about it here:
http://sourceforge.net/mailarchive/forum.php?thread_name=4941A8C4.7070206%40smoors.de&forum_name=hydrogen-devel
Here is how I installed Hydrogen from the new repository today on my 8.10 Intrepid system (you'll need the QT libraries, libqt4-dev if you don't already have them, as well as build-essential and probably a few others I'm forgetting):