No GSSAPI Output Token without GSS_C_MUTUAL_FLAG

[Michael B Allen <mba2000@ioplex.com>]

I've noticed that gssapi/gss_krb5_accept_sec_context() will not create
an output token if the AP-REQ does not request mutual authentication. As
a result gss_accept_sec_context returns 0 with an empty output token. Is
this correct? Shouldn't an AP-REP be sent back if only to say "ok"?

Mike