I'm sure this has been seen before, but after extensive googling & searching the mailing list archives, I found no solution.

The machine is Redhat 7.0, (much updated), running courier 0.42.0.20030319 compiled from source.

Using 'to' in a user's .mailfilter causes maildrop to return a signal 0x06. From the log: (unnecessary data replaced by <>)

<date/time> <host> courierlocal: id=<someid>,from=<<fromaddr>>,addr=<<user>@<host>>: maildrop: signal 0x06

<date/time> <host> courierlocal: id=<someid>,from=<<fromaddr>>,addr=<<user>@<host>>,status: deferred

It does execute the to command, but because of the signal courier assumes the command fails and requeues the mail for deferred delivery. The .mailfilter reads:

if ( /^X-Spam-Flag: YES/ ) { to Maildir/.Spam }

Why does it report signal 0x06?

I read several places that compiling with different compiler options fixed certain occurrences of this, but I compiled courier with the default optimisations, (-march=i686 -O2 -fomit-frame-pointer), on a PIII. I tried reducing it to -O and recompiling just maildrop, but to no avail.

Surely someone has solved this by now?