queues only come down with reboot

[Bart Smit]

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Strange problem which is starting to plague us more and more:

Two filters load balanced on MX. MailScanner 4.31.6. Dual Xeon 2.4 with 2GB RAM
First on RH9, sendmail 8.12.8-9.90
Second on FC1, sendmail 8.12.10-1.1.1

These process about 90k messages per day, usually with only a few messages
queued.