Hello Hal,
Thanks for your reply. I found the error (I'm CC-ing to the list
for the benefit of others).
The lines in .procmailrc which are giving the error are:
# remove duplicate mails (ie with same id number)
:0 Wh:/staff/sacha/.msgid.lock
| formail -D 8192 ~/.msgid.cache
^ This is not recognized by /bin/sh (or is it
formail after all?). If I put
| formail -D 8192 /staff/sacha/.msgid.cache
instead, then there are no problems
(apart from an inocuous
procmail: Extraneous locallockfile ignored
message, which was there before - anyone know why?)
Sacha