I have the same problem too. Xubuntu 11.04 final amd64 step to reproduce it:
1)Open Ubuntu Software Center 2)Search gstreamer0.10-plugins-mp3-fluedo-partner in the search bar 3)Click on "use this source" The crash appears -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/763716 Title: software-center crashed with ValueError in __init__(): Need either appname or pkgname or request -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs