That's because Tom applied a patch for this already:
http://archives.postgresql.org/pgsql-committers/2006-07/msg00080.php
//Magnus
> -----Original Message-----
> From: pgsql-ports-owner@postgresql.org [mailto:pgsql-ports-
> owner@postgresql.org] On Behalf Of Bruce Momjian
> Sent: Thursday, October 05, 2006 5:20 AM
> To: Henry B. Hotz
> Cc: Tom Lane; James.Gates@Sun.COM; pgsql-ports@postgresql.org
> Subject: Re: [PORTS] PostgreSQL and Kerberos 5 on Solaris
>
>
> I cannot find krb5_encrypt() referenced anywhere in configure, or
> anywhere else in CVS HEAD, nor in any of the back branches.
>
> -------------------------------------------------------------------
> --------
>
> Henry B. Hotz wrote:
> > Never saw a followup on this.
> >
> > I'd suggest krb5_init_context() since it's the first thing any
> > Kerberos app needs to do, and the returned context value is used
> on
> > 99% of all other calls. That's assuming that there aren't other
> > kerberos checks that make it unnecessary of course.
> >
> > On Jul 2, 2006, at 8:39 PM, Tom Lane wrote:
> >
> > > James Gates <James.Gates@Sun.COM> writes:
> > >> Does anyone know why the check for krb5_encrypt() exists in
> > >> configure when the code doesn't use it?
> > >
> > > At the time it was chosen, it was probably a reasonable choice
> of
> > > function to probe for to make sure Kerberos libraries are
> present.
> > > Do you have a better suggestion?
> > >
> > > regards, tom lane
> >
> > -----------------------------------------------------------------
> -----
> > --
> > ----
> > The opinions expressed in this message are mine, not those of
> Caltech,
> > JPL, NASA, or the US Government.
> > Henry.B.Hotz@jpl.nasa.gov, or hbhotz@oxy.edu
> >
> >
> >
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> --
> Bruce Momjian bruce@momjian.us
> EnterpriseDB http://www.enterprisedb.com
>
> + If your life is a hard drive, Christ can be your backup. +
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