You want to change a password using Kerberos from a Unix machine.
If you have MIT Kerberos 5 client installed and configured properly, you can run the following commands, which will change your password in Active Directory:
kinitPassword for jsmith@RALLENCORP.COM: **** $
kpasswdPassword for jsmith@RALLENCORP.COM: **** Enter new password: ****** Enter it again: ****** Password changed.
See Recipe 18.7 for more information on Kerberos.
MS KB 264480 (Description of Password-Change Protocols in Windows 2000), RFC 3244 (Microsoft Windows 2000 Kerberos Change Password and Set Password Protocols), and IETF draft-ietf-cat-kerb-chg-password-02.txt