I've had a look around and can't find any specific sites that show how to enable/use 'lazy mouse smoothing' on OSX.
EDIT: Unless this does the job (SmoothCursor): http://www.macupdate.com/app/mac/41736/smooth-cursor/ - have not used and am not affiliated with the app/company
SmoothCursor is a little utility that allows you to customize the acceleration settings of your mouse or trackpad separately. Totally recommended for drawing applications and FPS games*!
Developer's site: http://apps.leftbee.net/SmoothCursor
LazyNezumi itself states:
I’m sorry but there is no Mac support, and I don’t plan on ever providing any (this was already tricky enough to program for Windows, and I’ve never owned a Mac or programmed with them).