Solaris 9 is a little confused when it comes to security. It implements some cool features likes roles, RBAC and BSM auditing, but doesn't include decent password strength or password history checks. Luckily Solaris 9 does include PAM so these things can be added as modules.
Password cracking is easy, we just need to add a Solaris version of pam_cracklib, but I was unable to find a suitable module for password history. I decided to modify the pam_cracklib module to include a password history check...