Just a slight detour from our debugging stuff for some new info on credential roaming\DIMS ...
The size of the Ntds.dit file on the domain controller grows continually larger after you enable the "Credential Roaming" feature for Windows Vista-based client computers in the domain
Well now, that can't be good can it. If you use cred roaming for Vista clients - better get this on there.
VALUEON NUMERIC 1
PART !!DIMSCredentialRoaming_Vista TEXT
PART !!DIMSCredentialRoaming_Vista_Explain TEXT
PART !!DIMSCredentialRoaming_Box TEXT
PART !!DIMSCredentialRoaming_TombstoneValue NUMERIC REQUIRED
MIN 1 MAX 3650 DEFAULT 60 SPIN 30
PART !!DIMSCredentialRoaming_MaxNumTokens NUMERIC REQUIRED
MIN 1 MAX 10000 DEFAULT 2000 SPIN 100
PART !!DIMSCredentialRoaming_MaxTokenSize NUMERIC REQUIRED
MIN 1 MAX 100000 DEFAULT 65535 SPIN 1000
DIMS="Certificate Services Client"
DIMSCredentialRoaming_Explain="NOTE: If you want to configure Credential Roaming on a Windows Vista client, then don't use this policy. Instead use the Group Policy that is natively included in Windows Vista. \n\nThis policy setting specifies the behavior for user Credential Roaming.\n\nUser certificates and keys will be roamed and synchronized between the local user profile on the desktop and the user object in Active Directory when a user logs on interactively. \n\nIf you enable this policy setting, all X.509 certificates, keys, and enrollment requests will be uploaded and synchronized with the user object in Active Directory. You should also enable folder exclusion policies for roaming user profiles to avoid any conflicts in the use of multiple roaming technologies.\n\nIf this policy is enabled, then the Application Data folder should not be redirected using the Folder Redireciton technology. \n\nIf you disable this policy setting, all future synchronization and roaming will cease, but no keys or certificates will be deleted from the local user profile or Active Directory user object.\n\nIf you do not configure this policy setting, user certificate and key roaming will not be performed.\n\nNote: Folder exclusion policy settings may be configured in the user profiles section of the System administrative template.\n\n"
DIMSCredentialRoaming_Vista="NOTE: Not for environments with Vista clients."
DIMSCredentialRoaming_Vista_Explain="See Explain tab for more details."
DIMSCredentialRoaming_Box="Specific Credential Roaming settings:"
DIMSCredentialRoaming_TombstoneValue="Maximum tombstone credentials lifetime in days:"
DIMSCredentialRoaming_MaxNumTokens="Maximum number of roaming credentials per user:"
DIMSCredentialRoaming_MaxTokenSize="Maximum size (in bytes) of a roaming credential:"