cleaning up yahoogroups messages?

[Miles Fidelman <mfidelman@xxxxxxxxxxxxxxxx>]

Hi Folks,

I've been trying to migrate a collection of messages from yahoogroups to 
sympa (which uses mhonarc as it's archiving engine).

There's a great little script, yahoo2mbox, that pulls messages form 
yahoogroups and aggregates them into an mbox file - ideal for processing 
by mhonarc.

Unfortunately, when I run mhonarc on the mbox file, it seems to cut out 
the bodies of a lot of, but not all of the messages - leaving the header 
intact.  It seems like messages that originated with MS Outlook are 
particularly likely to end up with empty bodies.

Now I've read the archives of this list, and this seems to be a known 
problem with mhonarc filtering out malformed HTML, but I haven't seen 
any recent traffic indicating a solution of any sort.

So... has anybody come up with a straightforward way to clean up an mbox 
file sufficiently for mhonarc to process?  (e.g. a way to run the mbox 
file through HTML Tidy or some such)?  Or can anybody offer some 
suggestions, recipes, recent experiences, etc.?

Thanks much,

Miles Fidelman