~$ apt-cache policy thunderbird
thunderbird:
  Installiert: 11.0.1+build1-0ubuntu0.10.04.1~mts1
  Kandidat: 11.0.1+build1-0ubuntu0.10.04.1~mts1
  Versions-Tabelle:
 *** 11.0.1+build1-0ubuntu0.10.04.1~mts1 0
        500 http://ppa.launchpad.net/mozillateam/thunderbird-stable/ubuntu/ lucid/main Packages
        100 /var/lib/dpkg/status
     3.0.4+nobinonly-0ubuntu4 0
        500 http://archive.ubuntu.com/ubuntu/ lucid/main Packages