diff --git a/source4/scripting/python/samba/provision/__init__.py b/source4/scripting/python/samba/provision/__init__.py
index c414bd0..c00303a 100644
--- a/source4/scripting/python/samba/provision/__init__.py
+++ b/source4/scripting/python/samba/provision/__init__.py
@@ -561,7 +561,7 @@ def provision_paths_from_lp(lp, dnsdomain):
     return paths
 
 
-def guess_names(lp=None, hostname=None, domain=None, dnsdomain=None,
+def guess_names(lp=None, hostname=None, domain=None, dnsdomain=None, realm=None,
                 serverrole=None, rootdn=None, domaindn=None, configdn=None,
                 schemadn=None, serverdn=None, sitename=None):
     """Guess configuration settings to use."""
@@ -585,7 +585,10 @@ def guess_names(lp=None, hostname=None, domain=None, dnsdomain=None,
         raise InvalidNetbiosName(netbiosname)
 
     if dnsdomain is None:
-        dnsdomain = lp.get("realm")
+        if realm:
+		dnsdomain = realm
+        else:
+        	dnsdomain = lp.get("realm")
         if dnsdomain is None or dnsdomain == "":
             raise ProvisioningError("guess_names: 'realm' not specified in supplied %s!", lp.configfile)
 
@@ -598,7 +601,8 @@ def guess_names(lp=None, hostname=None, domain=None, dnsdomain=None,
 
     serverrole = serverrole.lower()
 
-    realm = dnsdomain.upper()
+    if realm is None:
+        realm = dnsdomain.upper()
 
     if lp.get("realm") == "":
         raise ProvisioningError("guess_names: 'realm =' was not specified in supplied %s.  Please remove the smb.conf file and let provision generate it" % lp.configfile)
@@ -1517,7 +1519,7 @@ def interface_ips_v6(lp, linklocal=False):
 
 def provision(logger, session_info, credentials, smbconf=None,
         targetdir=None, samdb_fill=FILL_FULL, realm=None, rootdn=None,
-        domaindn=None, schemadn=None, configdn=None, serverdn=None,
+        realm=None, domaindn=None, schemadn=None, configdn=None, serverdn=None,
         domain=None, hostname=None, hostip=None, hostip6=None, domainsid=None,
         next_rid=1000, dc_rid=None, adminpass=None, ldapadminpass=None, krbtgtpass=None,
         domainguid=None, policyguid=None, policyguid_dc=None,
@@ -1606,7 +1608,7 @@ def provision(logger, session_info, credentials, smbconf=None,
         lp = samba.param.LoadParm()
     lp.load(smbconf)
     names = guess_names(lp=lp, hostname=hostname, domain=domain,
-        dnsdomain=realm, serverrole=serverrole, domaindn=domaindn,
+        dnsdomain=dnsdomain, realm=realm, serverrole=serverrole, domaindn=domaindn,
         configdn=configdn, schemadn=schemadn, serverdn=serverdn,
         sitename=sitename)
     paths = provision_paths_from_lp(lp, names.dnsdomain)
diff --git a/source4/setup/provision b/source4/setup/provision
index 7140b26..e521332 100755
--- a/source4/setup/provision
+++ b/source4/setup/provision
@@ -54,6 +54,8 @@ parser.add_option_group(credopts)
 parser.add_option("--interactive", help="Ask for names", action="store_true")
 parser.add_option("--domain", type="string", metavar="DOMAIN",
 				  help="set domain")
+parser.add_option("--dnsdomain", type="string", metavar="DNSDOMAIN",
+				  help="set DNS domain")
 parser.add_option("--domain-guid", type="string", metavar="GUID", 
 		help="set domainguid (otherwise random)")
 parser.add_option("--domain-sid", type="string", metavar="SID", 
@@ -143,16 +145,16 @@ if opts.interactive:
 		default = socket.getfqdn().split(".", 1)[1].upper()
 	except IndexError:
 		default = None
-	opts.realm = ask("Realm", default)
-	if opts.realm in (None, ""):
-		print >>sys.stderr, "No realm set!"
+	opts.dnsdomain = ask("DNS Domain", default)
+	opts.realm = ask("Realm", opts.dnsdomain.upper())
+	if opts.realm in (None, "") and opts.dnsdomain in (None, ""):
+		print >>sys.stderr, "Realm or DNS Domain need to be set!"
 		sys.exit(1)
 
 	try:
 		default = opts.realm.split(".")[0]
 	except IndexError:
 		default = None
-	opts.domain = ask("Domain", default)
 	if opts.domain is None:
 		print >> sys.stderr, "No domain set!"
 		sys.exit(1)
@@ -165,9 +167,13 @@ if opts.interactive:
 		else:
 			break
 else:
+	if opts.dnsdomain in (None, ""):
+		opts.dnsdomain = sambaopts._lp.get('dnsdomain')
 	if opts.realm in (None, ""):
 		opts.realm = sambaopts._lp.get('realm')
-	if opts.realm is None or opts.domain is None:
+	if opts.dnsdomain is None or opts.realm is None or opts.domain is None:
+		if opts.dnsdomain is None:
+			print >> sys.stderr, "No DNS domain set!"
 		if opts.realm is None:
 			print >>sys.stderr, "No realm set!"
 		if opts.domain is None:
@@ -237,7 +243,7 @@ session = system_session()
 try:
 	provision(logger,
 		  session, creds, smbconf=smbconf, targetdir=opts.targetdir,
-		  samdb_fill=samdb_fill, realm=opts.realm, domain=opts.domain,
+		  samdb_fill=samdb_fill, dnsdomain=opts.dnsdomain, realm=opts.realm, domain=opts.domain,
 		  domainguid=opts.domain_guid, domainsid=opts.domain_sid,
 		  hostname=opts.host_name,
 		  hostip=opts.host_ip, hostip6=opts.host_ip6,