The MIT Kerberos team announces availability of daily snapshots of the development source tree, for developers only.
It is strongly recommended that if you use these sources in any way that beyond simply reading them for educational purposes that you join the krbdev mailing list (see the mailing lists page). The MIT Kerberos team makes no guarantees that these sources represent anything that will ever actually appear in a formal Kerberos release, or that they even vaguely come close to complying with various IETF and other standards which might otherwise apply to formal releases of Kerberos.
This is a DEVELOPMENT snapshot of the MIT Kerberos 5 sources, and is NOT intended for end users. It is NOT guaranteed to work, or even compile, on any given day. Contents under pressure. Keep out of reach of small children. Harmful or fatal if swallowed. No user-serviceable parts inside. Kludges in the source tree may be messier than they appear. Do not look into laser with remaining eye.
To obtain the krb5-current snapshot, use anonymous ftp to athena-dist.mit.edu and get the file /pub/kerberos/README.KRB5-CURRENT. It will contain instructions on how to obtain the krb5-current snapshot.
Documentation for krb5-current is here.