[MLton] Windows 7 x64 vs MLton r7999

[Matthew Fluet]

On Sat, 4 Jul 2009, Wesley W. Terpstra wrote:
> * msys uses an rxvt.exe which does not work under Windows7. Using msys
> -norxvt fixed this. I'll either modify the msys.bat to disable rxvt.exe or
> find a fixed rxvt.exe.

What purpose does msys.bat serve in the context of a MLton-NNNN.msi 
distribution?  If the user has mingw/msys installed, then won't it come 
with a msys.bat?  If the user doesn't have mingw/msys, then won't (the 
MLton) msys.bat not find any of the necessary executables?