jQuery.fn.innerWrap = function() {
    var a, args = arguments;
    return this.each(function() {
        if (!a) a = jQuery.clean(args, this.ownerDocument);
        // Clone the structure that we're using to wrap
        var b = a[0].cloneNode(true),
        c = b; 
        // Find the deepest point in the wrap structure
        while (b.firstChild) b = b.firstChild; 
        // append the child nodes to the wrapper
        jQuery.each(this.childNodes,
        function(i, node) {
            b.appendChild(node);
        });
        jQuery(this) 
        // clear the element
        .empty() 
        // add the new wrapper with the previous child nodes appended
        .append(c);
    });
};