ios UIActionSheet cancel button doesn't work right

I have this problem: here is my code:

UIActionSheet *popupQuery = [[UIActionSheet alloc] initWithTitle:@"Share the race" delegate:self cancelButtonTitle:@"Cancel" destructiveButtonTitle:@"Send with mail" otherButtonTitles:nil];
    popupQuery.actionSheetStyle = UIActionSheetStyleBlackTranslucent;
    [popupQuery showInView:self.view];
    [popupQuery release];

and everything seems ok, the 2 buttons are showed right, the "send with mail" button is ok, but the cancel catch the click only on the upper side... here a shot that illustrate the situation:

how can I solve this?

thanks:)