If youall are going to write this OpenBIOS thing in 32bit mode, I would like to offer up a C/C++ development environment that would suit this project nicely. Take a peek at uCR at http://www.picturel.com/ucrhome.html. Source is available, as are the compilers (EGCS) precompiled.
To make it go, someone would need to write a linker model and startup code. I already have thread switching for i386, but not interrupts. It is plenty small enough for the limited flash of a typical PC.
I have TCL 7.6 ported to this environment. This port is currently tied to the ISE board (a Picture Elements product) but I can fix that if there is demand.
It should be plausible to write call gates into 32bit code from 16 bit mode, but I don't really know.
If you think all the work should be done in 16bit mode, then I doubt this will be helpful.