I have problems with same topology over ACS. I have two domains in diferent Active Directory, we map those domains. Then in the Active Directory we create two groups for both domains. One for users names and passwords and another wich contains the PC names. We map those four groups in the same ACS for the diretens domanis maped there and we see that for one domain works the username maped and the PC names maped, and for the other domain only works for user domain names. Do you have any idea , or any documentation related with this cain of configuration?? Please any information that you can send to me it could be very important.