With this mod you will not have any problems with remapping keys. It is now possible to put one button multiple actions and everything will work. Very useful modification, I do not believe? Try it yourself, it works!
How to install Key Bindings Overhaul
- Download and install Minecraft Forge
- Download mod
- Do not unzip it, copy to C:\Users\User_Name\AppData\Roaming\.minecraft\mods