You could move with the times and make use of the money you've spent by letting the graphics card take over collisions by using NVidea's PhysX driver; which can be used with
Dark Dynamix or
Dark Physics.
There is a free version of Dark Dynamix available. Sparky's collision involves more work from you and your CPU.
There's is no sound reason to be using Sparky's collision, let alone explaining to your system how to handle character collision when it already knows; unless you are targeting out dated hardware.
As the wikipedia states:
Quote: "Middleware physics engines allow game developers to avoid writing their own code to handle the complex physics interactions possible in modern games. PhysX is one of the handful of physics engines used in all of today's games."