This is because these accounts are protected accounts. That is, they are
administrators, account operators, etc.
There is an object in the directory called the adminSDHolder object. The
PDCe compares and resets the permissions defined on this object against all
users who are members of protected groups every sixty minutes. Furthermore,
by default these groups are not set to inherit. Which is why they are still
grayed out even though you've granted write permissions.
There are a number of ways round this:
Modify the permissions on the adminSDHolder object
Remove these users from the protected groups.
Implement a hotfix from MS that changes this behaviour a little bit.
The reason for this (it's by design) is so that delegated users cannot
modify the permissions of administrative user objects.
If you search google or MS support for adminSDHolder you should find a
couple of helpful KBs.
--
Paul Williams
http://www.msresource.net/
http://forums.msresource.net/