Hello,

I solved an issue I had with Thunderbird not starting thought I would post in case others had same issue.

Fix:
The directory /usr/lib/thunderbird-2.0.0.9 needs to have "other" read and execute access turned on. Run the following command as root in terminal:
chmod o+rx /usr/lib/thunderbird-2.0.0.9

What the issue was:
On November 16 I updated Thunderbird to 2.0.0.9-1.fc7.i386 using pup,
since then Thunderbird would not start (from menu bar icon, nor from a terminal). When trying to start from terminal no messages were produced.

Regards