Here are a couple of solutions:
Both are easily setup and since you seem to have some technical ablilties you should be able to do either.
Let us know if you have any problems/questions.
This is what I know: The 6180 does not offer any encryption when emailing and gmail requires encryption. The only known work around is to use a service to wrap the outgoing emails in SSL to make gmail happy. The two suggestions I have seen on the boards are smtp2go.com and stunnel.org. I was able to sign up to smtp2go.com but it did not work. I still received the invalid from address error. stunnel.org looks beyond my technical ability.
Does any have another possible solution?
Oz