function change_src(link){
    var old_s = document.getElementById('dataloader');
    if (old_s){old_s.parentNode.removeChild(old_s);}
    var s = document.createElement('script');
    s.setAttribute('type', 'text/javascript');
	s.src = link;
	s.id = 'dataloader';
	document.getElementsByTagName('head')[ 0 ].appendChild(s);
}

InnerDiv.innerHTML = req.responseText;
doStart();

function doLoad(param) {
	var content = document.getElementById('content');
	content.innerHTML = 'Загрузка';
	change_src('administrator.js');
	var req = new JsHttpRequest();
	req.onreadystatechange = function() {
		if (req.readyState ==  4 ) {
			content.innerHTML = req.responseText;
			doStart(param);
		}
	}
	req.open(null, 'administrator.php', true);
	req.send();
}

req.onreadystatechange = function() {
	if (req.readyState ==  4 ) {
		content.innerHTML = req.responseText;
		alert('OK');
		doStart(param);
	}
}

req.onreadystatechange = function() {
	if (req.readyState ==  4 ) {
		content.innerHTML = req.responseText;
		doStart(param);
	}
}
req.onerror = function() {
...//как вывести ошибки??
}