Uncaught TypeError: Object function (){e.apply(this,arguments)} has no method 'walkPath'

[justinmakaila]

If i create a NestedModel within my models.js, anytime I attempt to update the model through code, I receive the above error. My model is instantiated like so:

var Special = Backbone.NestedModel.extend({
    initialize : function () {
        // Log the changed properties
        this.on('change', function (model, options) {
            for ( var i in options.changes)
                this.display();
            updateSession(model);
        });
        // Update session var
        this.updateSession(this);
    },
    //Attributes
    defaults : function () {
        return {
            "Product" : null,
            "ShortDescription" : null,
            "Category" : "food",
            "Price" : {
                "Regular" : null,
                "Special" : null,
                "PercentOff" : null
            },
            "Date" : {
                "StartTime" : null,
                "EndTime" : null,
                "HumanTimeRange" : null
            },
            "Uses" : 0,
            "Tags" : [],
            "Contributor" : null
        }
    },

    //Functions
    display : function (property) {
        console.log(property + ': ' + this.get(property));
    },
    displayAll : function () {
        console.log('Product: ' + this.get('Product'));
        console.log('ShortDescription: ' + this.get('ShortDescription'));
        console.log('Category: ' + this.get('Category'));
        console.log('Price: {');
        console.log('  Regular: ' + this.get('Price.Regular'));
        console.log('  Special: ' + this.get('Price.Special'));
        console.log('  PercentOff: ' + this.get('Price.PercentOff') + '\n}');
        console.log('Date: {');
        console.log('  StartTime: ' + this.get('Date.StartTime'));
        console.log('  EndTime: ' + this.get('Date.EndTime'));
        console.log('  HumanTimeRange: ' + this.get('Date.HumanTimeRange') + '\n}');
        console.log('Uses: ' + this.get('Uses'));
        console.log('Tags: ' + this.get('Tags'));
        console.log('Contributor: ' + this.get('Contributor'));
    },
    updateSession : function (model) {
        Session.set('NewSpecial', model);
    }
});

// Empty special to hold user entered data pertaining to new special creation
NewSpecial = new Special();

If i attempt to modify the contents with NewSpecial.set('Category', 'travel') I get the error. If i copy the same exact code but instantiate the model in the console, everything works fine. I'm using the backbone-nested.js as a smart package in Meteor (I packaged it myself and will upload it to Atmosphere for community use shortly).