Index: wp-includes/taxonomy.php
===================================================================
--- wp-includes/taxonomy.php	(revision 12478)
+++ wp-includes/taxonomy.php	(working copy)
@@ -1283,7 +1283,7 @@
 	else if ( 'all_with_object_id' == $fields )
 		$select_this = 't.*, tt.*, tr.object_id';
 
-	$query = "SELECT $select_this FROM $wpdb->terms AS t INNER JOIN $wpdb->term_taxonomy AS tt ON tt.term_id = t.term_id INNER JOIN $wpdb->term_relationships AS tr ON tr.term_taxonomy_id = tt.term_taxonomy_id WHERE tt.taxonomy IN ($taxonomies) AND tr.object_id IN ($object_ids) $orderby $order";
+	$query = "SELECT DISTINCT $select_this FROM $wpdb->terms AS t INNER JOIN $wpdb->term_taxonomy AS tt ON tt.term_id = t.term_id INNER JOIN $wpdb->term_relationships AS tr ON tr.term_taxonomy_id = tt.term_taxonomy_id WHERE tt.taxonomy IN ($taxonomies) AND tr.object_id IN ($object_ids) $orderby $order";
 
 	if ( 'all' == $fields || 'all_with_object_id' == $fields ) {
 		$terms = array_merge($terms, $wpdb->get_results($query));
@@ -1291,7 +1291,7 @@
 	} else if ( 'ids' == $fields || 'names' == $fields ) {
 		$terms = array_merge($terms, $wpdb->get_col($query));
 	} else if ( 'tt_ids' == $fields ) {
-		$terms = $wpdb->get_col("SELECT tr.term_taxonomy_id FROM $wpdb->term_relationships AS tr INNER JOIN $wpdb->term_taxonomy AS tt ON tr.term_taxonomy_id = tt.term_taxonomy_id WHERE tr.object_id IN ($object_ids) AND tt.taxonomy IN ($taxonomies) $orderby $order");
+		$terms = $wpdb->get_col("SELECT DISTINCT tr.term_taxonomy_id FROM $wpdb->term_relationships AS tr INNER JOIN $wpdb->term_taxonomy AS tt ON tr.term_taxonomy_id = tt.term_taxonomy_id WHERE tr.object_id IN ($object_ids) AND tt.taxonomy IN ($taxonomies) $orderby $order");
 	}
 
 	if ( ! $terms )