OD dropping members from Computer groups

Hello, We have a 10.6.3 OD master that has been dropping computers from computer groups. Over the past few weeks we've had a script that compares the GroupMembers, GroupMembership, Member, apple-group-memberuid and memberUid fields and alerts of any discrepancies between them. This week as we've been rolling out new computers we are seeing the problem happen. What I'm seeing: GroupMembers and apple-group-memberuid have been showing the drops, the other fields remain constant, the members tab of workgroup manager shows a "full" list. If I try to rebuild the membership list by deleting all the computers from the members tab and re-add them I do not get all 4 of those fields populated and need to resort to deleting and rebuilding the whole group entry from scratch. This week we've seen this happen several times it generally has affected machines that have been renamed by going into the computer record and manually changing the long and short name of the computer. Has anyone seen these symptoms or anything like it? Experience any specific problems when renaming computers in OD? Is there a best practice computer re-naming technique that's being missed? Thanks, Warren