MFMessageComposeViewController cancel button not working

I use this block to send message to the contacts, after sending, the back button is there, but when I touch it nothing happens. Please help me out :)

-(IBAction) InviteIt:(id) sender{


    if ([MFMessageComposeViewController canSendText]) {
        MFMessageComposeViewController *messageComposer =
        [[MFMessageComposeViewController alloc] init];
        messageComposer.messageComposeDelegate = self;
        NSString *message = @"You have more body buddies than you think at: http://www.itunes.com/app/JoyChain ";
        [messageComposer setBody:message];
        messageComposer.recipients = [NSArray arrayWithObjects:_itsnum, nil];
        messageComposer.messageComposeDelegate = self;
        [self presentViewController:messageComposer animated:YES completion:nil];

    }

}

Did you forget to implement mailComposeController:didFinishWithResult: ?...

- (void) mailComposeController:(MFMailComposeViewController *)controller didFinishWithResult:(MFMailComposeResult)result error:(NSError *)error
{
    switch (result)
    {
        case MFMailComposeResultCancelled:
            NSLog(@"Mail cancelled");
            break;
        case MFMailComposeResultSaved:
            NSLog(@"Mail saved");
            break;
        case MFMailComposeResultSent:
            NSLog(@"Mail sent");
            break;
        case MFMailComposeResultFailed:
            NSLog(@"Mail sent failure: %@", [error localizedDescription]);
            break;
        default:
            break;
    }

    // Close the Mail Interface
    [controller dismissViewControllerAnimated:YES completion:nil];
}

From apple documentation:

// The mail compose view controller delegate method
- (void)mailComposeController:(MFMailComposeViewController *)controller
              didFinishWithResult:(MFMailComposeResult)result
              error:(NSError *)error
{
    [self dismissModalViewControllerAnimated:YES];
}

But you can handle all cases depend on your goal ...