This is out of topic, but I would just like to strongly recommend you to stay far, far away from .bat scripts. They have been the cause of numerous time-consuming bugs in our development.
There's simply too many good alternatives out there to keep using the very, very badly designed script language remnant of DOS.
Usually bat files evolve from one-liners into multi-line scripts, which is where they start to generate bugs and generally just suck.
Use python, ruby, scheme, lisp, C#, whatever the heck you want, just DON'T use bat files.