Account access lost after backup and restore

[falk]

Something maybe related was reported by slickmrick a while ago:

MacBookPro, Superduper, OSX 10.4.8:

* SD backup/erase of all files onto external Firewire Drive
* Upgrade MBP 80GB internal drive to 160GB
* Installation of System 10.4.5 on internal drive using System CDs (cause previously I managed to corrupt my Character Palette using monolingual, so I wanted a proper system back)
* In the installation process you are invited to restore data from an "old mac" which I did by using the external drive as "old mac"
* Now I had most of my files back on System 10.4.5. I noticed, however, that many files were missing in some of the unix folders like /usr, /usr/bin, /usr/lib aso. Hence
* I booted from the external drive and applied SD "smart restore of all files which are newer or different". Many files were restored onto the internal drive
* After reboot, 3/6 user accounts were missing from the login window
* More badly, I had no access any more in System Preferences,Accounts on any account including my own
* I could only survive by re-installation from scratch, OSX-update by internet and restauration of missing files by hand

Did I miss something or is there a problem for SD to restore the privileges in files relevant for user accounts ?