title: Error fetching OAuth2 access token : 500 Error
body: <p>I am being randomly bugged by the following error message:<br>
  This occurs when <a href="http://code.google.com/p/google-api-php-client/" rel="nofollow">php library</a> tries to obtain the <a href="http://code.google.com/p/google-api-php-client/source/browse/trunk/src/auth/apiOAuth2.php" rel="nofollow">access token</a> line 112.  </p>
  
  <p>Sometimes my code obtains access token in first try, sometimes I need to refresh the URL containing 'code' as get parameter multiple times before access token is obtained. </p>
  
  <p>This error is coming frequently for last 3-4 days. </p>
  
  <pre><code>Fatal error: 
  Uncaught exception 'apiAuthException' with message 'Error fetching OAuth2 access token, message: 
  '&lt;HTML&gt; &lt;HEAD&gt; &lt;TITLE&gt;Error processing OAuth 2 request&lt;/TITLE&gt; &lt;/HEAD&gt; 
  &lt;BODY BGCOLOR="#FFFFFF" TEXT="#000000"&gt; 
  &lt;H1&gt;Error processing OAuth 2 request&lt;/H1&gt; 
  &lt;H2&gt;Error 500&lt;/H2&gt; 
  &lt;/BODY&gt; &lt;/HTML&gt; 
  '' in /google-api-php-client-0.5.0/google-api-php-client/src/auth/apiOAuth2.php:105
   Stack trace: #0 /google-api-php-client-0.5.0/google-api-php-client/src/apiClient.php(138): apiOAuth2-&gt;authenticate(Array) 
  #1 l.php(191): apiClient-&gt;authenticate() 
  #2 l.php(99): googoauthinit(true) 
  #3 {main} thrown in /google-api-php-client-0.5.0/google-api-php-client/src/auth/apiOAuth2.php on line 105
  </code></pre>
  
  <p>The code I use is directly lifted from <a href="http://code.google.com/p/google-api-php-client/source/browse/trunk/examples/userinfo/index.php" rel="nofollow">here</a> (EXACTLY same code with all parameters like app name, secret key, id etc correctly filled).
  Also, tried registering new app but same error is received.</p>