If only! GC pad support is most of the reason I'm playing more Goldeneye than black ops.
But that'd be quite a hack to make for a game, I doubt it will be done. Maybe if they developers coded in gamecube support but disabled it, maybe an Ocarina code could unlock it. But that is a HUGE if, and would be hard to crack anyhow.
Maybe an IOS hacked to reinterpret GC input as a Classic Controller? Also a huge piece of coding hell, I would imagine.