title: "qx.Class is undefined" when loading a qooxdoo application in source mode
body: <p>When loading a qooxdoo application in source mode, I obtain the following chain of javascript errors:</p>
  
  <p>qx.Class is undefined
  [Break on this error] qx.Class.define("qx.lang.Object",
  Object.js (ligne 24)</p>
  
  <p>qx.Class is undefined
  [Break on this error] qx.Class.define("qx.lang.Type",
  Type.js (ligne 23)</p>
  
  <p>qx.lang is undefined
  [Break on this error] errorToString : qx.lang.Object.select(
  Core.js (ligne 61)</p>
  
  <p>qx.core.Property is undefined
  [Break on this error] qx.core.Property.attach(clazz);
  Class.js (ligne 1478)</p>
  
  <p>qx.lang.Type is undefined
  [Break on this error] (qx.lang.Type.isObject(value) || typeof value === "object");
  Assert.js (ligne 632)</p>
  
  <p>qx.lang.Type is undefined
  [Break on this error] qx.lang.Type.isFunction(value) || this.__fail(
  Assert.js (ligne 504)</p>
  
  <p>qx.lang.Type is undefined
  [Break on this error] qx.lang.Type.isFunction(value) || this.__fail(
  Assert.js (ligne 504)</p>
  
  <p>qx.lang.Type is undefined
  [Break on this error] qx.lang.Type.isFunction(value) || this.__fail(
  Assert.js (ligne 504)</p>
  
  <p>qx.log.Logger is undefined
  [Break on this error] qx.log.Logger.register(statics);
  Native.js (ligne 119)</p>
  
  <p>qx.lang.Type is undefined
  [Break on this error] (qx.lang.Type.isObject(value) || typeof value === "object");
  Assert.js (ligne 632)</p>
  
  <p>qx.lang.Object is undefined
  [Break on this error] statics.FROM_CHARCODE = qx.lang.Object.invert(statics.TO_CHARCODE)
  String.js (ligne 447)</p>
  
  <p>qx.lang.Type is undefined
  [Break on this error] qx.lang.Type.isString(value) || this.__fail(
  Assert.js (ligne 518)</p>
  
  <p>qx.lang.Core is undefined
  [Break on this error] Stack.prototype.indexOf = qx.lang.Core.arrayIndexOf;
  BaseArray.js (ligne 496)</p>
  
  <p>qx.log.Logger is undefined
  [Break on this error] qx.log.Logger.deprecatedConstantWarning(
  ITableModel.js (ligne 268)</p>
  
  <p>qx.locale.Date is undefined
  [Break on this error] MONTH_YEAR_FORMAT : qx.locale.Date...teTimeFormat("yyyyMMMM", "MMMM yyyy")
  DateChooser.js (ligne 111)</p>
  
  <p>Note that those errors have been obtained with Qooxdoo 1.0 and 1.0.1, Firefox 3.6 and Firebug 1.5.2.
  I tested with Internet Explorer and I obtain the same kind of javascript errors.</p>
  
  <p>From my understanding, it seems that the js files are not loaded / evaluated in the right order.</p>
  
  <p>Below is the order in which the js files are loaded:
  index.html
  ria.js
  RemoteProxy.js
  engine.js
  util.js
  Bootstrap.js
  Setting.js
  Engine.js
  __System.pageLoaded.dwr
  Variant.js
  Object.js
  Type.js
  Aspect.js
  Class.js</p>
  
  <p>In build mode, everything works as expected.</p>