One of these buttons is also a third mouse button. There are a few arcane tools and drivers that you can buy to get around this. The Rodent driver allowed you to add switches to your config.sys file to try and tune it to the specific device. It's a bit old, though, and doesn't work well with many of the new mice or digitizer tablets. I'm not a programmer, so I honestly can't tell how difficult or easy this would be to accomplish, but it seems as if it would be easier than creating a universal display adapter.
Mice are pretty simple.
If it's a standard mouse, it plugs into a serial port. If it's a USB mouse, it plugs into a USB port. When you click on the left mouse button, it sends some kind of signal to the port. If you click on the right mouse button, it sends a different kind of signal to the port. If you move the mouse up or down, or from side to side, it sends different signals to the port.