This could be rightfully construed as a beginner's question.
Consider the following e-mail header:
MIME-Version: 1.0
My Questions:
- When should use stamp an e-mail with this header?
- When should you omit this e-mail header?
EDIT: Is it true that whenever you specify a 'Content Type' header, no matter what that content type happens to be, that you should also specify 'MIME-Version'? [This link tipped me off to the possibility.]