title: Wake lock does not seem to work
body: <p>I'm developing an app in which i need the TCP connection to stay alive. I've implemented a kind of ping/pong system to do this. It works perfectly when the screen is on, but when it goes of the phone stops responding to the pings after a while. I've created a Wi-Fi wake lock but i'm still experiencing still the same problem..</p>
  
  <p>This is my code:</p>
  
  <pre><code>private static WifiManager wm = getSystemService(this.WIFI_SERVICE);
  private static WifiLock wl = null;
  
  public static void lock(){
      wl = wm.createWifiLock(WifiManager.WIFI_MODE_FULL , App.TAG);
      if(!wl.isHeld()){
          wl.acquire();
      }
  }
  
  public static void unlock(){
      if(wl != null){
          if(wl.isHeld()){
              wl.release();
          }
      }
  }
  </code></pre>
  
  <p>Any ideas?</p>