The rc-script contains:
echo -n "Starting vchkpw pop daemon: qmail-pop3"
ulimit -v 2048
sh -c "start-stop-daemon --start --quiet --user root \
--exec $DAEMON -- \
-H -R 0 pop-3 \
/usr/sbin/qmail-popup "$HOSTNAME" /usr/sbin/vchkpw \
/usr/sbin/qmail-pop3d Maildir &"
I've managed he's worked by commenting out ulimit line