probably an error in lua 5.2 alpha in luaD_rawrunprotected

[pk pk <pkairevent@...>]

While trying to implement LuaThread 1.1 (by Diego Nehab) to Lua 5.2 alpha
under linux 2.6.x, I'm always getting segfault in function luaD_rawrunprotected.
It arises when im launching lua like this: lua -e "print(123)"

When I'm commenting parts, that locking/unlocking lua_State mutex,
segfault disappears! I dont know why, need help!

here is a patch file that implements only problem part: http://pastebin.com/aipzPv3n

commenting this parts: lua_lock(L), lua_unlock(L)
segfault appears here:   LUAI_TRY(L, &lj,    (*f)(L, ud);  );