Index: wp-includes/taxonomy.php
===================================================================
--- wp-includes/taxonomy.php	(revision 12141)
+++ wp-includes/taxonomy.php	(working copy)
@@ -690,7 +690,10 @@
 	if ( !empty($include) ) {
 		$exclude = '';
 		$exclude_tree = '';
-		$interms = preg_split('/[\s,]+/',$include);
+		if ( is_array($include) )
+			$interms =& $include;
+		else
+			$interms = preg_split('/[\s,]+/',$include);
 		if ( count($interms) ) {
 			foreach ( (array) $interms as $interm ) {
 				if (empty($inclusions))
@@ -721,7 +724,10 @@
 		}
 	}
 	if ( !empty($exclude) ) {
-		$exterms = preg_split('/[\s,]+/',$exclude);
+		if ( is_array($exclude) )
+			$exterms =& $exclude;
+		else
+			$exterms = preg_split('/[\s,]+/',$include);
 		if ( count($exterms) ) {
 			foreach ( (array) $exterms as $exterm ) {
 				if ( empty($exclusions) )