Hi.
I have also been doing some reading on the Internet concerning this problem and it seems to be related to the AD security used to identify the user.
When the profiles are originally created in the SSP during and import, the username and SID (Security Identifier) is stored in the SSP database from AD (Acitve Directory). It seems that if any changes occurr on AD after this fact and the SID's are changed, then Sharepoint gets confused.
The only way I can see in fixing this would be to delete the user profile and do and re-import from AD. Unfortunately this is not always feasible as the user most likely has information stored in their "My Site" that they would like to keep.
Microsoft has recently release a new "Administration Toolkit v2.0" for Sharepoint that has tools in it to migrate and export user profiles and "My Sites". it can be donwload from here: http://www.microsoft.com/downloads/details.aspx?FamilyID=263cd480-f6eb-4fa3-9f2e-2d47618505f2&displaylang=en
Once you have installed the toolkit, there will be a tool called "User Profile Replication Engine". Give it a try and let me know. You might have to setup a new temporary SSP for this to work.
Neil van Wyngaard is a MCSE, MCSD, MCDBA, MCT, MCTS, MCITP, MCBMSS. Neil's core industry focus is CRM, ERP, EPM and ECM implementations in the enterprise environment. Core technology focus is based on SQL Server, Visual Studio, WSS, MOSS and OCS