Comment 8 for bug 470193

On karmic 64-bit, I changed a line in /usr/bin/mousetrap from python2.5 to python and now it works for me.

This is how I did it from the command line:

$ sudo gedit /usr/bin/mousetrap

Search for "python" (there's only 1 occurrence). Replace "python2.5" with "python" and you're good to do.