Description:
------------
This is related to http://bugs.php.net/bug.php?id=21687.
I believe the tests used to determine whether auth_gss gets invoked aren't working right.

As distributed in the tarball, auth_gss gets defined in imap.so, but it doesn't appear to get used.  To make GSSAPI authentication work, I need to move 

  auth_link(&auth_gss); /* link in the gss authenticator */

out of..

  #if HAVE_IMAP_KRB && defined(HAVE_IMAP_AUTH_GSS)
  #endif

otherwise, our ticket files don't ever get IMAP credentials.

Reproduce code:
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$mbox = imap_open( "\{imap.example.com:143/imap/notls/user=" 
    . $user . "}INBOX", $user, $passwd ); 

(our servers, currently some flavor of UW IMAP seem to require the extra "user=" in the connection string)

Expected result:
----------------
We should get two things...
- a kerberos credential cache w/ IMAP credentials
- an open IMAP stream authenticated w/ GSSAPI

Actual result:
--------------
The ticket file remains unchanged, and the IMAP servers return  "AUTHENTICATE GSSAPI FAILURE"