[exim] broken exim - local mail is going out smtp

Hello,

I have a centos 6 server that runs exim for SMTP and dovecot for
pop/imap to my clients. Very recently and for unknown reasons, inbound
SMTP to this server (user@???) is, instead of being delivered to
a local mailbox (/var/spool/mail/user), is now attempted to be delivered
out to the internet via smtp:

 exim -bt user@???
user@???
  router = dnslookup, transport = remote_smtp
  host example.com [xxx.xxx.xxx.xxx]
  host example.com [xxx.xxx.xxx.xxx]                    

I have no config changes I know about, I have even went back to old
backups to verify /etc/exim/exim.conf has remained untouched and this is
so. I can not find any other config or system change and am at a
complete loss to understand why my local domain (example.com) is now
suddently considered remote and mail delivery attempted via smtp?

       My domain uses a spam filtering service and my mail host is
hidden. If you do a MX lookup on my domain (example.com), you will get
the MX's of the spam filter service. So the flow here is, internet ->
spam filter service -> direct SMTP to my mail host, which then receives
the mail and does an MX lookup, finds records pointing to the spam
filter service and tries to forward there. But it should just take the
mail and stuff it in local boxes.


    Im at my wits end. Help!


Thank you.


Mike-