printer stoppages

[Mark Brophy]

Hi:
We're having problems here with CUPS frequently stopping printers.  After the printer is stopped, jobs fill up in the queue and eventually have to be removed when we restart the printer.  The thing is, I don't want the printer to stop in the first place.  I saw that more than a few people have a shell script as a cronjob that restarts all stopped printers, but this is not a reasonable solution for us.  It seems that when the printers go to sleep, the problems begin.  So my questions are
1) What's the purpose/benefit of this behavior?
2) How can I disable it?

The printers in question are all HP LaserJets by brand: 4200,4500,etc, and I have a custom backend written, heavily based on PyKota.  It's to my understanding that if this returns a nonzero result, then the printer will also be stopped.  If anyone could offer some insight into this problem, it would be highly appreciated.

Thanks,
-Mark