UIActionSheet on iPad is not showing cancel button

I am trying to show cancel button in UIActionSheet but it's not showing, is that an acceptable behavior? please advice.

UIActionSheet *actionSheet = [[UIActionSheet alloc]
          initWithTitle:@"Are you sure you want to clear the cache?"
          delegate:self
          cancelButtonTitle:@"No"
          destructiveButtonTitle:@"Yes"
          otherButtonTitles:nil];

[actionSheet showInView:self.view];  

[actionSheet release];