They are flakey, see
http://git.samba.org/autobuild.flakey/2011-04-28-1501/samba4.stdout
http://git.samba.org/autobuild.flakey/2011-04-28-1700/samba4.stdout
metze
Autobuild-User: Stefan Metzmacher <metze@samba.org>
Autobuild-Date: Thu Apr 28 18:42:06 CEST 2011 on sn-devel-104
# ktutil might not be installed or from mit...
# we should build a samba4ktutil and use that instead
samba4.blackbox.ktpass # this test isn't portable ...
+s3member # this tests sometimes fail to start the environment