Is it possible to add new biomes (like mesa, giant mushrooms, ...) to the beta1.7.3 world generator and keep the old Far lands?

I'm going to implement new experimental biome generator (Currently this biome generator is part of Minecraft mod I'm working on, still unfinished).
It will allow all MInecraft biomes to be generated in beta 1.7.* worlds without terrain shape difference.

Great, thanks.