Added lengthFieldClass indirection
diff --git a/dev/js/src/match/treemenu.js b/dev/js/src/match/treemenu.js
index 16f6306..fec7703 100644
--- a/dev/js/src/match/treemenu.js
+++ b/dev/js/src/match/treemenu.js
@@ -18,7 +18,7 @@
     create : function (info, params) {
       var obj = Object.create(menuClass)
 	.upgradeTo(this)
-	._init(itemClass, undefined, params);
+	._init(itemClass, undefined, undefined, params);
       obj.limit(6);
       obj._info = info;