Persisting json data in jstree through postback via asp:hiddenfield

Question

I've been pouring over this for hours and I've yet to make much headway so I was hoping one of the wonderful denizens of SO could help me out. Here's the problem...

I'm implementing a tree via the jstree plugin for jQuery. I'm pulling the data with which I populate the tree programatically from our webapp via json dumped into an asp:HiddenField, basically like this:

JavaScriptSerializer serializer = new JavaScriptSerializer();
string json = serializer.Serialize(Items);

json = json.ToLower();
data.Value = json;    

Then, the tree pulls the json from the hidden field to build itself. This works perfectly fine up until I try to persist data for which nodes are selected/opened. To simplify my problem I've hardcoded some json data into the tree and attempted to use the cookie plugin to persist the tree state data. This does not work for whatever reason. I've seen other issues where people need to load the plugins in a specific order, etc, this did not solve my issue. I tried the same setup with html_data and it works perfectly. With this working persistence I converted the cookie plugin to persist the data in a different asp:hiddenfield (we can't use cookies for this type of thing in our application.)

essentially the cookie operations are identical, it just saves the array of nodes as the value of a hidden field. This works with the html_data, still not with the json and I have yet to be able to put my finger on where it's failing.

This is the jQuery.cookie.js replacement:

jQuery.persist = function(name, value) {
    if (typeof value != 'undefined') { // name and value given, set persist
        if (value === null) {
            value = '';
        }
        jQuery('#' + name).attr('value', value);
    } else { // only name given, get value
        var persistValue = null;
        persistValue = jQuery('#' + name).attr('value');
        return persistValue;
    }
};

The jstree.cookie.js code is identical save for a few variable name changes. And this is my tree:

$(function() {
                $("#demo1").jstree({
                    "json_data": {
                        "data" : [
                        {
                            "data" : "A node",
                            "children" : [ "Child 1", "Child 2" ]
                        },
                        {
                            "attr": { "id": "li.node.id" },
                            "data" : {
                                "title": "li.node.id",
                                "attr": { "href": "#" }
                            },
                            "children": ["Child 1", "Child 2"]
                        }
                    ]
                    },
                    "persistence": {
                        "save_opened": "<%= open.ClientID %>",
                        "save_selected": "<%= select.ClientID %>",
                        "auto_save": true
                    },
                   "plugins": ["themes", "ui", "persistence", "json_data"]
                });
            });

The data -is- being stored appropriately in the hiddenfields, the problem occurs on a postback, it does not reopen the nodes. Any help would be greatly appreciated.

After looking through this some more, I just wanted to explain that it appears to me that the issue is that the tree has not yet been built from the JSON_data when the persistence operations are being attempted. Is there any way to postpone these actions until after the tree is fully loaded?