How to open a prettyPhoto lightbox automatically when the page loads?

Question

I am really new to Jquery and I have found several examples of opening a light box using cookies and the the onload feature. I am using the cookie example which works with fancybox, but I have been using prettyPhoto on all my sites and really do not want to change to fancybox. I have tried a dozen different ways to get this to work but I have no luck. Here is my code. Any help or suggestions would be great.

$(document).ready(function(){

// !!! SEE THIS PLEASE !!!
// delete this line to make the modal box load only ONCE
// if you let it set to 'false' it will show every time .. set it to 'true' and it will never show
$.cookie("modal", 'false')

/**
  *  MODAL BOX
  */
// if the requested cookie does not have the value I am looking for show the modal box
if($.cookie("modal") != 'true')
{
    alert("sometext");

var where = "http://images.motortrend.com/photo_gallery/112_0611_39z+2006_bugatti_veyron+interior.jpg"; var title = ""; var comment = "";

function showLbox(){ $.prettyPhoto.open(where, title, comment); } // on page load show the modal box // more info about the options you can find on the fancybox site

    // in the message is a link with the id "modal_close"
    // when you click on that link the modal will close and the cookie is set to "true"
    // path "/" means it's active for the entire root site.. if you set it to "/admin" will be active on the "admin" folder
    // expires in 7 days
    // "modal" is the name i gave the cookie.. you can name it anything you want
    $('#modal_close').live('click', function(e) {
        e.preventDefault();
        $.cookie("modal", "true", { path: '/', expires: 7 });


    });
}

});