title: Google App Engine - recompile GWT module
body: <p>I've created <strong>Google App Engine</strong> project in Java using Eclipse following the book <em>Beginning Java Google App Engine</em></p>
  
  <p>Before I bought this book I had created projects with unchecked option '<strong>Use Google Web Toolkit</strong>' but for this project I checked it (following the book)</p>
  
  <p>Eclipse generated several files for me and I run my applications, copy link to Web Browser (<code>http://localhost:8888</code>) and it gives me an error:</p>
  
  <blockquote>
    <p>GWT module name_of_my_project may need to be (re)complied</p>
  </blockquote>
  
  <p>I work on <strong>Ubuntu 10.04</strong> (I was testing my application using Firefox and Chromium) and I was trying run my application on Windows XP (using the same Web Browsers) with the same effect (just one difference - Google Chrome made me install Web Toolkit...so I did it but it still gives the same error)</p>
  
  <p>Thanks in advance :)</p>