[Exim] Periods in the middle, and suggestions for quotas usi…

(currently using exim3, migrating to 4 over the next short while)

I'm more comfortable for the time being monkeying with this in version 3
than 4, but if this is easier in 4, it can be the kick in the butt to
get me to go to 4 more quickly..

I'm wanting to find out how to do address's with a period between the
first and last names? I saw something regarding using a "+" in the
example configs, but wasn't really to get a lot from it... Can someone
post me an example, or at least a description of what I should to do
make this possible?

And the other question is quotas on maildir. I know courier has
deliverquota, is it best to let exim determine if the quota has been
exceeded, courier, or the OS (freebsd)?