Guess what ? Your custom kernel is also unsupported.
But my changes will be minimal and can be easily documented/explained to management. If it shows up with unsupported in the name, a lot of people will be alarmed. I wish we could call it something else -- perhaps "plus" or "extended" instead of "unsupported".
Get the src.rpm, install it, edit the spec, rebuild.
Wrinse and repeat, MaZe.