Just to write if someone else need this service....
I've found that DynDNS have MailHop service (paid service).
And just to clarify my needs
I'm maintaining two eBox servers and want all error to come on my company account (external)
Is this a good idea? Is there any other way to do that?
Tnx
Just another add
We can accomplish sending e-mails outside the eBox using gmail.
If someone is interesting I'll write a HowTo.