Single user login help

I am a Windows 2003 Admin and have been tasked with integrating 3 Mac 10.4.8 servers into our Network. I have read the white paper from this site and have made progress with the AD integration. My issue is thst when I sit at my Windows Xp workstation and use a UNC path to the Mac server, I still get a login in prompt? Looking at the "Windows File Serve Log" on the Mac I see "odssam_getsampwnam:(get_sam_record_attributes dsRecTypeStandard:Users no account for '[i]username[/i]"! In the Terminal in the Mac I can issue the Kinit command and receive a proper output. I type Kinit [i]username[/i] Enter password for username@domainname.com is returned. I enter the correct PW and the command completes with no errors. Klist shows a ticket in cache. Workgroups manager is pulling the domain user and group lists from my AD. What have I missed? I am a complete newbe here so I am open to all input. Dsipp