mouse wheel support question

[Daren Lim]

I've implemented a feature for an application that uses the mouse wheel on
the Windows.
I need to code it for XWindows. From what I have read so far the wheel sends
mouse button 
presses of 4 and 5 in Xwindows.  

I'm not sure if trying to test through Cygwin is 
not letting me detect the messages in XWindows or if there is another 
reason.  I found that for XFree86 4.2 "The mouse driver now has support 
for mouse wheel emulation."   

I tried xdyinfo | grep release 
to figure out which version of XFree86 I'm running...
it returned "vender release number : 40200000

So do I need to update my Xfree86 version ?  

Thanks,
dAren