Telnetd does not offer KERBEROS_V5 authentication

[Jason C. Wells]

When I attempt to telnet to a FreeBSD 10.3 host, the telnetd does not 
offer KERBEROS_V5 as an authentication method. With debugging turned on, 
I see only:

    td: recv suboption AUTHENTICATION IS NULL CLIENT | ONE-WAY

inetd.conf  has 'telnetd -a valid'. The host principal exists and has 
been added to the telnetd host's keytab. Pam is configured to enable 
pam_krb5. 'ldd /usr/libexec/telnetd' shows that libkrb5 is linked.

How do I enable Kerberos authentication for telnetd in FreeBSD 10.3?

Regards,
Jason C. Wells