title: A simple facebook app gets Method Post is not allowed error
body: <p>I tried a very simple helloworld example facebook app. Basically I have a webpage, only contains one file index.php, which only contains one line: echo "helloworld". I have registered this app as an facebook app, configured the setting, canvas url to <a href="http://mydomain/" rel="nofollow">http://mydomain/</a>..</p>
  
  <p>I can load the page mydomain/index.php. However, when I load the page <a href="http://apps.facebook.com/appid" rel="nofollow">http://apps.facebook.com/appid</a>, I got the following error:
     The requested method POST is not allowed for the URL ...</p>
  
  <p>I checked apache config, there is no  or  settings to prevent POST method.</p>
  
  <p>Apache error log ad access log does not say anything.</p>
  
  <p>Do you have any clue how to fix this?</p>
  
  <p>Thanks for your kind help!</p>