Reinstall bash on MacOS 10.7 I have a MacBook Air where someone attempted to install this version of bash over MacOS's native one unknowingly. I attempted to fix this by removing the files created by the installer (the readme was clear about it).

This version was causing error because it's compiled for PowerPC, so I immediately deleted it. Now I'm lacking Bash.

I'd use my system install disk to restore it, but I'm on an MBA and I'm not sure how to proceed from here. Any help is appreciated.
If this someone did everything which is documented in the referenced article, you should be able to get your old bash back by 


Opening Terminal.app (which will give you an error because it can't start bash)
Running another shell directly via "Shell -- New Command" (Shift-Cmd-N) (e.g. /bin/ksh)
Executing sudo mv /bin/bash-old /bin/bash