I have tried to repro your issue in our environment without success. Most of the similar issues I had with my Perl programs related to looking up SIDs out of context where the old domain did not exist.
Create a new user account in the domain. This will ensure there is no SID history associated with it. Add the new account to a group and then use a test script with a single INGROUP to check membership. Does the error still get logged?
If not, look for a program called LDP.exe. Use it to review all the properties and attributes rtelated to a user's account SID history to see if anything is left over.
[ 06. May 2003, 00:05: Message edited by: Howard Bullock ]
