I never installed SME in domain controller, but I can say that there are no wins server on SME !
Maybe you should set DNS to SME's IP on your workstations
For 2000/2003 servers it's needed !
On your workstations, your domain should looks like cac.yourdomain.com and not cac "alone" - Again, I have not tested this mode so maybe I am thinking just like M$ taught me
I guess the best you can do is activate DHCP server on SME so that you don't need to worry for your workstations' configurations - Just set it to DHCP !
Hope this helped