Problem _WinApi_PostMessage()

Hi to all, I've a problem with post message function.
I want to simulate a mouse click on a window:

PHP Code:


			
;Mousemove
_WinAPI_PostMessage ($BGAPI_HWND, 0x200, $x, $y)
;Mousedown
_WinAPI_PostMessage ($BGAPI_HWND, 0x201,$x, $y)
;Mouseup
_WinAPI_PostMessage ($BGAPI_HWND, 0x202, $x, $y)

I've used that code, but the script always click in the wrong point.. why?

I'm sure that I put something wrong in the last 2 params. But How can I make it work?

Thanks ;)