In Minecraft, is there no way to recreate a world that was generated in an older update?

I have this world I really like, and it still has a seed that you can look at in F3. I really want to recreate it to the way it was before I added anything to it.

I know clicking the re-create world option doesn't work for this.

Yes, i have done this before ALTHOUGH! There's a mod that allows you to use the past generation code to generate worlds from earlier updates. I happened to love the Glacier seed in early alpha i believe it was!