iOS 4, Voip

I have a VOIP application.  It runs in the background as per the Apple docs.

On thing is interesting.  In the handler for my input and output streams I have this code:

     if ([ UIApplication sharedApplication ].applicationState == UIApplicationStateActive)
      {
        NSLog(@"APPSTATE: UIApplicationStateActive");
      }
      else if ([ UIApplication sharedApplication ].applicationState == UIApplicationStateInactive)
      {
        NSLog(@"APPSTATE: UIApplicationStateInactive");
      }
      else if ([ UIApplication sharedApplication ].applicationState == UIApplicationStateInactive)
      {
        NSLog(@"APPSTATE: UIApplicationStateInactive");
      }
      else
      {
        NSLog(@"APPSTATE: Unknown: %d", [ UIApplication sharedApplication ].applicationState);
      }

According to the headers the only allowable values for "applicationState" are  UIApplicationStateActive, UIApplicationStateInactive, and UIApplicationStateBackground.

So when my app is in background with TCP/IP running it prints out

  APPSTATE: Unknown: 2

So it seems like the background VOIP state is 2.  An undocumented state at that!