From
MS knowledge base:
"If you log on to an MIT realm, press CTRL+ALT+DELETE, click Change Password, type your existing MIT password, and then type a new, simple password that does not pass the dictionary check in Kadmind, you may receive the following error message:
Your password must be at least 18770 characters and cannot repeat any of your previous 30689 passwords. Please type a different password. Type a password that meets these requirements in both text boxes.
..."
[Via
aumund.org]