Create two Windows domains, one for servers and the other one for XP workstationand laptops.    The best way to achieve this is to use the the standard FQDN for the servers account ie: example.com, with say username of server_admin and then create a second collection domain that uses the NETBIOS resolved name for the same Windows domain for the workstations ie: EXAMPLE with the username of workstation_admin.

You can refine it further by using $Domains and specifiying the fully qualified domain as part of the username eg: server_admin@example.com or example.com\server_admin. $Domains assume localhost for authentication, but the fully qualified username will force the local machine to authenticate via the domain controller.