mouse wheel scroll in scroll window

[Richard Gipps <rgipps netspace net au>]

I wish to use the wheel on the mouse to zoom in and out on my 
application. This application involves a scroll window, so I want normal 
scrolling action when the wheel is used on it's own or a zooming action 
when you press control and use the wheel. The problem is the scroll 
window seems to 'take' the scroll event. How can I take the scroll event 
when the control button is pressed and leave it when the mouse wheel is 
used without the control key?

Richard Gipps.