jQuery Grid Plugin - jqGrid

Hi, i use IE 8, i copied the demo folder into my www folder and i've modified the dbconfig.php file and when i try to execute any of the examples like "editing.html" in my web server apache it doesn't show any grid it just appear the button control, the status bar says the editing.js file is waiting for an object. this happens in every demo, plz help, i have tried to add the $(document).ready(function() at the top of the editing.js file but it keeps the same it just showed the button control.