Expand All Nodes on Lazyload in Jquery dynatree

Question

I am using Dyna Tree plugin for tree view.

Now, while expanding the parent node I am using lazy load function,

onLazyRead: function(node){
    node.appendAjax({
    url: TREEVIEW_JSON_URL
    });
}

Now I would like to expand all the child and sub-child nodes those are available in my response with lazyLoad. In the current scenario I am able to expand only child nodes.

Please help me out on this. Thanks in advance