is it possible to make longjmp-free Lua?

["Juris Kalnins" <juris@...>]

I'm thinking whether it is possible to modify Lua so that it doesn't do  
setjmp/longjmp stack unwinding.
One idea is to set some "bad flag" in the state on throw, indicating that  
evaluation should short-circuit until it gets either to nearest try, or to  
top level.
I did not find any patch or discussion about this. Has anyone attempted  
this before? How large could be the required the change to the internals?