Notes converting incorrectly entered internet address

We have a problem with Notes converting incorrectly entered internet address and causing problems.

user types in incorrect email address:

big_boss@internet…com

(Note the two dots)

notes smtp server looks at this and converts it to

big_boss%internet…com@myDomain.com

This then gets stuck in our mimesweeper server which does not know how to handle it so dumps it in a folder and does not send a failure.

I want to know if it possible to stop the domino smtp server converting this and just passing it on straight as it is.

I know you could say this is a mimesweeper problem but it is easier to get an answer and fix for the notes servers than for mimesweeper.

Thanks for any help you can give me.