pam_krb524 is a PAM session module which gets the user Kerberos 4 tickets on login using krb524init, and removes them on logout. One uses the module by adding the line
session optional pam_krb524.so
in /etc/pam.d/common-session after pam_krb5.so. It supports the debug option.
pam_krb524 is part of the Debian-Athena distribution. You can also browse and download the source. The current version, pam_krb524 1.2, was released on July 24, 2007.