Mac session timeouts on Win2003 Svr - 12061

I have a new Win2003 Svr running 50 or so PCs and 8 Macs. All of the
Macs will get session timeouts at different times during the day,
usually 10-12 timeouts/day total. These show up in the event viewer
on the Win2003 Svr as Event ID 12061. And obviously the users on the
Macs must re-authenticate to the Windows server to get back to any
shares. Every Mac seems to have the problem and there is a wide
assortment of hardware- powerbook, emacs, imacs. All of them are
running either OS 10.2 or 10.3, no OS 9's left on the network. I see
no errors on my 3com switches, and have tried moving some to other
switches/hubs with no effect.

Is anyone else seeing this out there with their Macs?


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