iOS4上的uiImagePickerController崩溃

当试图显示uiImagePickerController时,我的应用程序在iOS4上崩溃了,这有点奇怪。以下是日志的输出:

malloc: *** error for object 0x550ba20: pointer being freed was not allocated
*** set a breakpoint in malloc_error_break to debug

设置断点,试图监视对象0x550BA20(带有打印对象)的名称不起作用。启用僵尸检测也不起作用。这是我的代码:

if([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera]) {

  cameraPicker = [[UIImagePickerController alloc] init];
  cameraPicker.delegate = self;

  cameraPicker.sourceType = UIImagePickerControllerSourceTypeCamera;

  // Insert the overlay:
  cameraPicker.cameraOverlayView = self.overlay;
  self.cameraPicker.delegate = self;

  //Hide controls
  cameraPicker.showsCameraControls = NO;
  cameraPicker.navigationBarHidden = YES;

  // Make camera view full screen:
  cameraPicker.wantsFullScreenLayout = YES;
  cameraPicker.cameraViewTransform = CGAffineTransformScale(self.cameraPicker.cameraViewTransform, 1.0, 1.12412);


  [self presentModalViewController:cameraPicker animated:NO];
  [cameraPicker release];

有什么想法吗?代码在viewdidload的最后执行。