title: Error using Zend_Http_Client on GoogleAppEngine
body: <p>I'm developing a web app on Google app engine, using php and zend. 
  When I try to run <code>Zend_Http_Client</code> to connect to another application on Google app engine written in Java I get an error:</p>
  
  <blockquote>
    <p>Unable to Connect to tcp://****.appspot.com:80. Error #-1: Unknown error 4294967295.</p>
  </blockquote>
  
  <p>Billing is enabled for both applications so everything should work fine. Any ideas what could be causing this error?</p>