How are you obtaining this information? Is it with a login script that maps to other servernames sporadically, or is it something different?
Are you in a WAN environment using Active Directory, or an NT4 domain (PDC, BDC running DNS/WINS)?
Sounds like your leases are expiring on the primary domain controller due to lack of syncronization, and therefore grabbing the BDC's copy (outdated perhaps) to authenticate the user. Check the eventlogs on the DC and BDC to confirm this...check WINS (if applicable) for tombstoned computer accounts, and DHCP for lease durations.
Hope this helps..
Pbxman
Systems Administrator
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