This can be recreated on 8.04.1, but it seems to be an issue with the
.msf files. If you simply delete the .msf files within your ~/.mozilla-
thunderbird directory the files will be recreated and then the correct
emails will begin showing up again. Apparently the profile is being
corrupted somehow.
Yes. Since I first posted the solution of deleting the .msf file the
same problem has occurred on the machine at least a dozen times. At this
point my father has abandoned using thunderbird and now does all his
email online. The computer is now using 9.04 and the issue is still
persistent. It would