[Exim] exim 4 newbie: can't receive mail

I just installed exim4 on red hat7.2. I can send mail out through pine just
fine (local and world wide). But I can't receive mail on the localhost. I
see my message in the spool but it isn't getting forwarded to the file I
specified in the conf. Here are some settings I have from the config:

local_delivery:
driver = appendfile
file = /var/spool/mail/${local_part}
delivery_date_add
envelope_to_add
return_path_add
group = mail
mode = 0660

I copied parts of the config file from other sites but nothing seems to
work.

-thanx, ryan