Log Message:
Update thunderbird and thunderbird-gtk1 to 1.5.0.8.  Fixed in this version:

MFSA 2006-67 Running Script can be recompiled
MFSA 2006-66 RSA signature forgery (variant)
MFSA 2006-65 Crashes with evidence of memory corruption (rv:1.8.0.8)

For more info, see http://www.mozilla.com/en-US/thunderbird/releases/1.5.0.8.html