title: No source code is available for type <xyz>; did you forget to inherit a required module?
body: <p>I'm trying to add a <a href="https://code.google.com/p/gwt-cal/" rel="nofollow">dependency</a> to my GWT project. The problem is that I am getting the following error:</p>
  
  <pre><code>[INFO] --- gwt-maven-plugin:1.0-beta-2:codeserver (default-cli) @ mahlzeit-web ---
  [INFO] Turning off precompile in incremental mode.
  [INFO] Super Dev Mode starting up
  [INFO]    workDir: E:\java\mahlzeit-web\mahlzeit-web\target\gwt\codeserver
  [INFO]    Loading Java files in com.mahlzeit.web.App.
  [INFO]    Tracing compile failure path for type 'com.mahlzeit.web.GoogleCalendarPanel'
  [INFO]       [ERROR] Errors in 'file:/E:/java/mahlzeit-web/mahlzeit-web/mahlzeit-web-client/src/main/java/com/mahlzeit/web/GoogleCalendarPanel.java'
  [INFO]          [ERROR] Line 54: No source code is available for type com.bradrydzewski.gwt.calendar.client.Calendar; did you forget to inherit a required module?
  [INFO]          [ERROR] Line 161: No source code is available for type com.bradrydzewski.gwt.calendar.client.event.DeleteHandler&lt;T&gt;; did you forget to inherit a required module?
  [INFO]          [ERROR] Line 162: No source code is available for type com.bradrydzewski.gwt.calendar.client.event.DeleteEvent&lt;T&gt;; did you forget to inherit a required module?
  </code></pre>
  
  <p>I know I would have to add something like <code>&lt;source ...&gt;</code> to my <code>App.gwt.xml</code> file but that is <em>generated</em>. I am using the <a href="https://github.com/tbroyer/gwt-maven-archetypes" rel="nofollow">gwt-maven-archetypes</a> in Eclipse.</p>
  
  <p>How can I add this dependency s.t. the GWT Compiler finds the sources in the library <code>.jar</code> file? </p>