Are there any plans to backport Fiber to ruby 1.8?

I have a working pure ruby implementation that relies on ruby threads
(http://gist.github.com/4631), but am interested in a more performant
and light weight implementation like the one in 1.9.

What would be involved in getting cont.c to compile under ruby 1.8?
Are there other ways of saving and restoring context in 1.8 without
using threads?

  Aman