[exim] MX config

Hello,

I am fairly new to Exim, so please be patient ;)

I want to set up an standard MX server for some customer domains based
on a MySQL database. How could a "standard configuration" look like?

Additionally: Is it possible to use a different smarthost _only_ to
send out bounces? If so, can you give me some hints on how to do that?

Thank you and regards,
Dietmar