Try this :
UIActionSheet *popupSheet = [[UIActionSheet alloc] initWithTitle:@"Title"
delegate:self
cancelButtonTitle:@"Cancel"
destructiveButtonTitle:@"No Way !"
otherButtonTitles:nil];
popupSheet.actionSheetStyle = UIActionSheetStyleBlackOpaque;
UIButton * disclosureButton = (UIButton *)cell.accessoryView;
[popupSheet showFromRect:disclosureButton.bounds inView:cell.accessoryView animated:YES];
[popupSheet release];
the showFromRect:inView:animated: method displays the action sheet in a popover whose arrow points to the specified rectangle of the view (in our case the detail disclosure button). The popover does not overlap the specified rectangle.