I'm playing Minecraft on a mac, and I'm using a Logitech Revolution MX. When scrolling in the game, it flicks through my items very quickly, rather than one item-per-click scrolling than I get in Windows. Is there any way to get sensible scrolling through items?
The hardware button should properly switch between smooth scrolling and single line scrolling, irrespective of the OS its plugged into. I'm not sure why its not working for you.
That said, Logitech Control Center is now supported in OSX, and it works with the Revolution MX. With this installed, you should be able to tweak the scrolling behavior.
It's a little old, but for anybody searching for a solution, I got a pretty decent one:
Logitech's Control Center is the one doing it! Remove it from your settings / uninstall it. I discovered this after doing a clean install and playing Minecraft for the first time.
To configure which button does what you can use the free and much more advanced software Better Touch Tool. There are no problems at all when using BTT instead of Logitech's Control Center and there are many more options.