Mark Weaver writes:
> I have my .forward file set up to automatically insert mailing-list
> mail in their respective folders using rcvstore.  One of the things
> that rcvstore does is add the new messages to the "unread" sequence.
> If I happen to modify a sequence in the same folder at the same time,
> and file locking isn't working, I'd expect this kind of corruption.

If by "unread" you mean the "Unseen-Sequence" take a look at the BUGS
section of rcvstore(1)'s manpage:

BUGS
       If  you  use the "Unseen-Sequence" profile entry, rcvstore
       could try to update the context while another  MH  process
       is  also  trying  to do so.  This can cause the context to
       become corrupted.  To avoid this, do not use  rcvstore  if
       you use the "Unseen-Sequence" profile entry.

> Also, "packf" consistently dumps core for me.
Bug in dropsbr.c.  H=E5vard Eidnes' fix below.

*** dropsbr.c.FCS	Wed Dec  1 05:01:35 1993
--- dropsbr.c	Fri May  5 11:33:09 1995
***************
*** 178,182 ****
  int	mbx_read (fp, pos, drops, noisy)
  register FILE  *fp;
! register long	pos;
  struct drop **drops;
  int	noisy;
--- 178,182 ----
  int	mbx_read (fp, pos, drops, noisy)
  register FILE  *fp;
! off_t		pos;
  struct drop **drops;
  int	noisy;

					-jarle
----
"If it makes goo on the windshield, we'll call it a bug."
				-- Larry Wall