diff --git a/src/item/Item.js b/src/item/Item.js
index e6edddbb..147e9b3f 100644
--- a/src/item/Item.js
+++ b/src/item/Item.js
@@ -319,6 +319,10 @@ var Item = Base.extend(Callback, /** @lends Item# */{
 		// parent's children object:
 		if (this._name)
 			this._removeNamed();
+		// See if the name is a simple number, which we cannot support due to
+		// the named lookup on the children array.
+		if (name === (+name) + '')
+			throw 'Names consisting only of numbers are not supported.'
 		if (name && this._parent) {
 			var children = this._parent._children,
 				namedChildren = this._parent._namedChildren,