Index: wp-includes/category.php
===================================================================
--- wp-includes/category.php	(revision 8875)
+++ wp-includes/category.php	(working copy)
@@ -37,14 +37,14 @@
  * @return array List of categories.
  */
 function &get_categories( $args = '' ) {
-	$defaults = array( 'type' => 'category' );
+	$defaults = array( 'type' => 'category', 'taxonomy' => 'category' );
 	$args = wp_parse_args( $args, $defaults );
 
-	$taxonomy = 'category';
 	if ( 'link' == $args['type'] )
-		$taxonomy = 'link_category';
-	$categories = (array) get_terms( $taxonomy, $args );
+		$args['taxonomy'] = 'link_category';
 
+	$categories = (array) get_terms( $args['taxonomy'], $args );
+
 	foreach ( array_keys( $categories ) as $k )
 		_make_cat_compat( $categories[$k] );