More usefully, use whatever you have locally as seed and fetch it from
It should hopefully manage to install on the new dual-core G5 machines,
and it also has a rebuilt Thunderbird package, which we've been waiting
for for a number of months. This still isn't an _official_ update but it
does the job.
I'd very much like to hear from you if you tried it on a dual-core G5.
Especially if it worked.