MozillaThunderbird: Update to Thunderbird 3.1.11 (important)

Mozilla Thunderbird was updated to the 3.1.11 release. It has new features, fixes lots of bugs, and also fixes the following security issues: MFSA 2011-19/CVE-2011-2374 CVE-2011-2376 CVE-2011-2364 CVE-2011-2365 Miscellaneous memory safety hazards MFSA 2011-20/CVE-2011-2373 bmo617247 Use-after-fre...