Cargar fichero JS después de que haya cargado otro

chainable external javascript file loading.js

/**
*
*  Chainable external javascript file loading
*  http://www.webtoolkit.info/
*
**/
scriptLoader.load([
'http://ajax.googleapis.com/ajax/libs/jquery/1.3.2/jquery.min.js',
'http://ajax.googleapis.com/ajax/libs/jqueryui/1.7.2/jquery-ui.min.js'
'your-script.js'
]);
 
 
var scriptLoader = {
    _loadScript: function (url, callback) {
        var head = document.getElementsByTagName('head')[0];
        var script = document.createElement('script');
        script.type = 'text/javascript';
        script.src = url;
        if (callback) {
            script.onreadystatechange = function () {
                if (this.readyState == 'loaded') callback();
            }
            script.onload = callback;
        }
        head.appendChild(script);
    },
 
    load: function (items, iteration) {
        if (!iteration) iteration = 0;
        if (items[iteration]) {
            scriptLoader._loadScript(
                items[iteration],
                function () {
                    scriptLoader.load(items, iteration+1);
                }
            )
        }
    }
}