MouseX and MouseY on a Canvas

MouseX() and MouseY() aren't returning coords on a canvas. =(

I was expecting MouseX/Y, too, before I found EventX() and EventY(). Here's how I do it:

Select EventSource()
	Case canvas
		Local mx, my
		Select EventID()
			Case EVENT_MOUSEMOVE
				mx = EventX()
				my = EventY()

Ah... Sneaky...