I can not join domain from VISTA ultimate to SAMBA V3.024. I got error from VISTA as below.

" The following error occurred attempting to join the domain sky.local
The specified account already exists. "

here is log from SAMBA

" pdb_get_group_sid:Failed to find Unix account for SP-DELL$"

How can I fix this problem ? I use root account to join domain,it works well with WinXP user.