Index: languages/languages_item.php
===================================================================
--- languages/languages_item.php	(revision 13168)
+++ languages/languages_item.php	(working copy)
@@ -60,8 +60,14 @@
 		{
 			$default = false;
 			if ($id == 'default') {
-				$id = 1;
-				$id_field_name = 'PrimaryLang';
+				// domain based primary language
+				$id = $this->Application->siteDomainField('PrimaryLanguageId');
+
+				if (!$id) {
+					$id = 1;
+					$id_field_name = 'PrimaryLang';
+				}
+
 				$default = true;
 			}
 
Index: themes/theme_item.php
===================================================================
--- themes/theme_item.php	(revision 13168)
+++ themes/theme_item.php	(working copy)
@@ -20,8 +20,14 @@
 		{
 			$default = false;
 			if ($id == 'default') {
-				$id = 1;
-				$id_field_name = 'PrimaryTheme';
+				// domain based primary theme
+				$id = $this->Application->siteDomainField('PrimaryThemeId');
+
+				if (!$id) {
+					$id = 1;
+					$id_field_name = 'PrimaryTheme';
+				}
+
 				$default = true;
 			}