[Evolution] Error when clicking on email address

[Dianne Reuby <pramclub yahoo co uk>]

If I click on an email address shown in an incoming email, I'm getting
the following error:

Failed to execute child process /usr/lib/thunderbird-3.0.6/thunderbird
No such file or directory

I did install tbird some months ago to try when Evo was giving some
problems, but uninstalled it quite soon afterwards. I've upgraded my
Ubuntu from 10.04 to 10.10 since then. My Evo is 2.30.3

TIA

Dianne