[VM] Sorting does not mark a folder as changed?

[Daniel Barrett]

Sorting a folder doesn't seem to count as a change to the folder in VM
8.2.0b.

1. Visit a VM folder.

2. Type "G" to sort the messages, and choose a sort that's different
from the current one.

3. The buffer's status bar doesn't get marked as changed: no "**" appears
in the lower left. Typing "S" to run vm-save-and-expunge-folder has no
effect. Closing and reopening the folder shows that the sort didn't
get saved.

I think the behavior was different when I ran Emacs 23 rather than 24.
Is this behavior configurable?

Thanks,
Dan

--
Dan Barrett
address@hidden