Index: wp-includes/bookmark-template.php
===================================================================
--- wp-includes/bookmark-template.php	(revision 22313)
+++ wp-includes/bookmark-template.php	(working copy)
@@ -209,6 +209,10 @@
 		'category_after' => '</li>'
 	);
 
+	if ( empty( $args['category'] ) ) {
+		$args['categorize'] = 0;
+	}
+	
 	$r = wp_parse_args( $args, $defaults );
 	extract( $r, EXTR_SKIP );