Cast categoryId to string to be compliant. fixes #3662

git-svn-id: http://svn.automattic.com/wordpress/branches/2.1@4807 1a063a9b-81f0-0310-95a4-ce76da25c4cd

xmlrpc.php

@@ -977,7 +977,7 @@ function mt_getPostCategories($args) {
 		foreach($catids as $catid) {
 			$categories[] = array(
 				'categoryName' => get_cat_name($catid),
-				'categoryId' => $catid,
+				'categoryId' => (string) $catid,
 				'isPrimary' => $isPrimary
 			);
 			$isPrimary = false;