qmail-smtpd     Receive message by SMTP from another host:                        |             MAIL FROM:<joe@heaven.af.mil>     |             RCPT TO:<bill@irs.gov>     |               |          Is $RELAYCLIENT set? Yes: "".     |          Accept RCPT.       V                                qmail-queue     Store message safely on disk.                Trigger qmail-send.     |                  V                                qmail-send      Look at envelope recipient, bill@irs.gov.     |          Is irs.gov in locals? No.     |          Is bill@irs.gov in virtualdomains? No.     |          Is irs.gov in virtualdomains? No.     |          Is .gov in virtualdomains? No.     |          Deliver remotely to bill@irs.gov.     V                             qmail-rspawn    Run qmail-remote.     |                  V             qmail-remote    Look at host name, irs.gov.                Is irs.gov listed in smtproutes? No.		Look up DNS MX/A for irs.gov and connect to it by SMTP:                                      MAIL FROM:<joe@heaven.af.mil>                   RCPT TO:<bill@irs.gov>