nnml corruption in move to emacs 21?

[Todd H.]

Greetings, 

I was recently forced into an upgrade of Emacs for the first time in
a few years.   My last emacs was 20.6. 

Now, I have a hugemongous nnml directory for spam thats over 30,000
messages since I rarely bother to go in there unless I'm hunting for
something specific.

I've just noticed that when I moved my home directory to this new
machine, though, something appears to have gotten corrupted in that
subdirectory so when I access this nnml group, only the messages since
the switchover are viewable.

The older messages show up in the message window are garbled, almost
like I'm looking at something uuencoded or compressed.  And, if I look
at the actual files on the disk now, they look similarly garbled, so
it's not just a display issue. 

So, am I chasing down a file corruption issue, or did something change
in Gnus perhaps that might have modified nnml message store, or is
there a known issue when nnml message counts get over a certain
threshhold, or ??? 

TIA for any insight or advice! 

Best Regards, 
-- 
Todd H.
http://www.toddh.net/