commit 86c3a79a108091fe08869a887438cc2d4e1126ed
Author: Neil Brown <neilb@suse.de>
Date:   Wed Aug 27 16:30:19 2008 -0400

    mount issue with Mac OSX and --manage-gids, client hangs
    
    Make sure are zero len group list is sent down to the
    kernel when the gids do not exist on the server.
    
    Tested-by: Alex Samad <alex@samad.com.au>
    Signed-off-by: Neil Brown <neilb@suse.de>
    Signed-off-by: Steve Dickson <steved@redhat.com>

diff --git a/utils/mountd/cache.c b/utils/mountd/cache.c
index f555dcc..609c6e3 100644
--- a/utils/mountd/cache.c
+++ b/utils/mountd/cache.c
@@ -158,8 +158,10 @@ void auth_unix_gid(FILE *f)
 		qword_printint(f, ngroups);
 		for (i=0; i<ngroups; i++)
 			qword_printint(f, groups[i]);
-	}
+	} else
+		qword_printint(f, 0);
 	qword_eol(f);
+
 	if (groups != glist)
 		free(groups);
 }