I've uploaded https://bitbucket.org/dryeo/dry-comm-esr24/downloads/thunderbird-24.8.1b3.en-US.os2.7z
This is based on the same Gecko code as the Bitwise Firefox beta 4 release with the addition of libsydneyaudio to re-enable HTML5 sound. Requirements are the same.
Note that due to combining mozjs.dll into xul.dll, Lightning needs to be updated.
https://bitbucket.org/dryeo/dry-comm-esr24/downloads/lightning-2.6.5r2.en-US.os2.xpi

Note that I've seen some instability with both TB and SM xul.dlls loaded into high memory. I haven't really tested Firefox much but be aware.

Dave Yeo