Wheel scroll left / right?

Hi

Is there currently any way to get a mouse wheel scroll left or right?
Currently the event seems to be picked up as SDL_BUTTON_WHEELUP and
SDL_BUTTON_WHEELDOWN.

In many modern mice, there is a wheel (or buttons) for scrolling
left / right and up / down. More specifically, for the Apple line of
products, whether it’s the Macbook trackpad or Mighty Mouse,
scrolling left and right is inherently tied in to scrolling up and
down since they are not separate buttons but a single movement on the
pad or ball. This makes it VERY disconcerting to the user if he
intends to scroll up-down but accidentally shifts it a bit left-right
(which is quite common).

Is there some way to pick up the scroll left or right events? Or at
least ignore LEFT / RIGHT movements so that they aren’t being sent as
UP / DOWN.

Thanks!
Rick