Log Message:
Update thunderbird and thunderbird-gtk1 to 1.5.0.10.  Fixed in this version:

MFSA 2007-06  Mozilla Network Security Services (NSS) SSLv2 buffer overflow
MFSA 2007-01 Crashes with evidence of memory corruption (rv:1.8.0.10/1.8.1.2)

For more info, see http://www.mozilla.com/en-US/thunderbird/releases/1.5.0.10.html