jquery.fancytree/demo/ajax-sub.xml

Fancytree is a JavaScript tree view plugin for jQuery with support for persistence, keyboard, checkboxes, drag'n'drop, and lazy loading.

<children>
	<node lazy="true">
		<title> SubNode 1 (lazy)</title>
	</node>
	<node folder="true" lazy="true">
		<title> SubNode 1 (lazy)</title>
	</node>
</children>