[exim] closing banner and relays

Hi all,

I'd like to change the closing banner and I am not sure where to look for
it.
Currently it says: 221 $primary_domain closing connection

Also does anyone know how to change the welcome banner according to the
receiving interface (IP)? I have exim listening on different IP addresses
and I'd like it to respond appropriately - to have all domain related info
set to this IP's reverse DNS if possible

And lastly, I am sending a copy of each email to certain domains to a backup
email address, using driver = redirect in router config, the email address
set as file = /etc/exim4/copy_mail/$domain but I can't figure out the
correct syntax for a domain list file.
domains = domain1.com:domain2.com:domain3.com works fine but domains =
lsearch;/etc/exim4/relay_domains does not.
relay_domains contains a list of domains separated by LF


Thx for any insight
-src-