I've discovered why procmail gets stuck:

I setup a little script so that when I telneted into my box it dumped the
ulimits:

/other/home/neil:neil@NetBSD>telnet netbsd neiltest
Trying 158.152.1.20...
Connected to netbsd.demon.co.uk.
Escape character is '^]'.
time(seconds)        unlimited
file(blocks)         unlimited
data(kbytes)         16384
stack(kbytes)        512
coredump(blocks)     unlimited
memory(kbytes)       59608
locked memory(kbytes) 19870
process(processes)   40
nofiles(descriptors) 64
Connection closed by foreign host.

That limit of processes and fd's is just way too low, inetd is setting them
when it forks (?) there must be a way to increase this? ( I run sendmail
from inetd as it is part of our security policy)

Regards,
Neil

-- 
Neil J. McRae.                                       Demon Internet
neil@demon.net