Changing the sensitivity of the scrollwheel on Magic Mouse for gaming?

Hello,

I know how to adjust the sensitivity for the wireless Magic Mouse as far as the number of vertical lines onscreen that a swipe will scroll past, but my question pertains to gaming... I'm playing Team Fortress 2 with my Magic Mouse and I like to set MWHEELUP & MWHEELDOWN to change weapons, but the tiniest flick of my index finger on the mouse will send me cycling through 3 or 4 weapons in a blink. I want to know if there's some way to force the Magic Mouse hardware to recognize a single, decent-sized, intentional flick of my finger across the length of the mouse as one "scroll" of the wheel, as opposed to having a single motion translate to several.

Hope that makes sense. There's no native feature for adjusting scrollwheel sensitivity within the game, as its pretty standard that most hardware mice with scrollwheels have some tactile feedback for what constitutes a single "scroll", but the Magic Mouse doesn't. So I appreciate it immensely if anyone can help me, thanks.