Compilation warnings? Code walker?

["Will Fitzgerald" <fitzgerald@neodesic.com>]

Probably 90% of my MzScheme errors are because I've misspelled an
internal procedure call, or misremembered it, or forgotten to load a
file.

For example, I might write:

(define (foo x) (kar x))

Forgetting that 'car' is spelt 'car', and not 'kar.'

MzScheme doesn't warn me, unfortunately, that 'kar' is not defined. If
it did, I would probably catch most of those errors I was talking about.

1. Is there some sort of compilation flag for MzScheme to warn me that
I'm not aware of?

2. Or has anyone defined a code walker to make these kind of warnings?