Index: wp-admin/ms-edit.php
===================================================================
--- wp-admin/ms-edit.php	(revision 15339)
+++ wp-admin/ms-edit.php	(working copy)
@@ -220,6 +220,7 @@
 					$allowedthemes[$theme] = true;
 			}
 		}
+
 		update_option( 'allowedthemes',  $allowedthemes );
 
 		// options
@@ -227,7 +228,7 @@
 			$c = 1;
 			$count = count( $_POST['option'] );
 			foreach ( (array) $_POST['option'] as $key => $val ) {
-				if ( $key === 0 || is_array( $val ) )
+				if ( $key === 0 || $key == 'allowedthemes' || is_array( $val ) )
 					continue; // Avoids "0 is a protected WP option and may not be modified" error when edit blog options
 				if ( $c == $count )
 					update_option( $key, stripslashes( $val ) );