Supplement 4 of the Server Resource Kit contains passprop.exe, a tool that helps you tighten security two ways:
/complex</b> Force passwords to be complex, requiring passwords
to be a mix of upper and lowercase letters and
numbers or symbols.
<b>/simple</b> Allow passwords to be simple.
<b>/adminlockout</b> Allow the Administrator account to be locked out.
Once the account is locked out, as in response to an attempted break-in,
it can still log on interactively on domain controllers.
<b>/noadminlockout</b> Don't allow the administrator account to be locked out.