Index: admin-ajax.php
===================================================================
--- admin-ajax.php	(revision 14853)
+++ admin-ajax.php	(working copy)
@@ -70,6 +70,7 @@
 		die; // require 2 chars for matching
 
 	$results = $wpdb->get_col( "SELECT t.name FROM $wpdb->term_taxonomy AS tt INNER JOIN $wpdb->terms AS t ON tt.term_id = t.term_id WHERE tt.taxonomy = '$taxonomy' AND t.name LIKE ('%" . $s . "%')" );
+	$results = apply_filters( "wp_ajax_{$taxonomy}-search", $results, $s);
 
 	echo join( $results, "\n" );
 	die;