OS 10.5 - "mach_kernel" file deleted, how to i get it back?!

Noticed a few days ago that I had a file named "mach_kernel" on the same level as my "applications" folder. I had no clue what it was and how it got there, so I deleted it. BIG mistake.

I've since learned that this essential file is supposed to be way burried somewhere. After restarting today i was unable to fully boot my system, and after half a days worth of research, i stumbled upon the mach_kernel idea (i then remembered i had deleted it).

I've completed a full Leopard reinstall, disc repair, etc. With no solution. I even tried booting a os9 disc in an attempt to boot to select it's system folder as my startup system, reboot and reinstall from osx disc and use the "mach_kernel" file from the os9 system folder. (this what the support page on apple.com suggests). No luck even booting the os9 disc. I now somehow unmounted the hard drive though.

Anyone have any help here?