Problems with Domain users group in Samba and LDAP

Hi We have installed a Samba network, using SLES 8 (sp3 with all updates). We use OpenLDAP( v. 2.1.4-86) as a backend for Samba (v. 2.2.8a-133). The clients are running Windows 2000 pro. In the OpenLDAP database we have created several Windows groups. One of those group is Domain Users. On the clients machines we have joined the Domain users group to local Administrator group. The group name joins correctly but the users do not get local Administrator rights on the computer. If we create the user in /etc/passwd and the Domain users group in /etc/groups then it works with Samba. Does anyone know a solution or a workaround to this problem? -- Jonas Helgi Palsson IT-Konsulent, Bergen kommune tlf: 5556 9810 / 950 44 932