title: PHP Session is not set using php & EXTJS
body: <p>When I call a php file using Ajax, I do this : </p>
  
  <pre><code>function logIntoApp(){
      Ext.Ajax.request({
          url:'php/login.php',
          params:{
                  action:'login',
                  email:Ext.getCmp('userLogin').getValue(),
                  motDePasse:Ext.getCmp('passwordLogin').getValue()
          },
          method:'GET',
          success:function(result, request){
              //Ext.MessageBox.alert('Success', );
              if(result.responseText == 'admin'){
                  //Ext.MessageBox.alert('Alert', result.responseText);
                  window.location.replace("administration.php");
              }
              else if(result.responseText == 'pro'){
                  //Ext.MessageBox.alert('Alert', result.responseText);
                  window.location.replace("proAdministration.php");
              }
              else{
                  Ext.MessageBox.alert('Alert', result.responseText);//'Email ou mot de passe incorrect!');
              }
          },
          failure:function(result, request){
              Ext.MessageBox.alert('Failed', 'Erreur de chargement de données');
          }
      });
  }
  </code></pre>
  
  <p>in my php file, I set a $_SESSION to use it in my administration.php</p>
  
  <pre><code>if($role=='Administrateur'){
                      $_SESSION['role']='admin';
                      $_SESSION['email']=$email;
                      $message = 'admin';
                  }
  </code></pre>
  
  <p>And in my administration.php, I have this : </p>
  
  <pre><code>&lt;?php
  session_start();
  echo "alert(''". $_SESSION['role'] . ")";
      if($_SESSION['role']=='admin'){
          //echo "alert('pro')";
      }
      else{
          //echo "alert('admin')";
          header("Location:index.php");
      }
  ?&gt;
  </code></pre>
  
  <p>And in my index.php I have this : </p>
  
  <pre><code>&lt;?php
  
      session_start();
      $_SESSION['role']='visiteur';
      $_SESSION['email']='no';
  
  
  ?&gt;
  </code></pre>
  
  <p>the problem is that I'm never redirected to administration.php, I think because the $_SESSION['role'] is never set as 'admin'</p>