/*
* this dynamically loads and replaces one image with another
* 
* @param id   		string		id of image to replace
* @param url  		string		url of img to load
* @param callback	function	callback function (function ref)
*
*
*/
function dynamicImageReplace(id,url,callbackSuccess, callbackError){
	document.images[id].src=url;
	if(callbackSuccess != null) document.images[id].onLoad=callbackSuccess;
	if(callbackError != null) document.images[id].onError=callbackError;
}