title: difference between a form post and $http.post()
body: <p>I am performing a post to a backend server which is an openid authentication library. It works when I have a simple form with its action pointing to the server url. </p>
  
  <p>However it fails when I use the $http.post method. I have compared the headers and changed the  content-type to url-form encoded. This resolves part of the problem, but the redirection from the server still fails.</p>
  
  <p>Any ideas on what are the differences between a regular form post and angular's $http.post which is causing this behavour ?</p>