.PS
# the new architecture

maxpswid = 6.0
linewid = 0.2
movewid = 0.3


I: [
down
I1: ellipse "sendmail"
move 0.2
I2: ellipse "smtpd"
move 0.2
I3: ellipse "..."
]

move

QI: ellipse "queue-in"
arrow up right
IQ: box dashed "incoming" "queue"
arrow
SC: ellipse "scanning"
arrow
OQ: box dashed "outgoing" "queue"
arrow down right
QO: ellipse "queue-out"

move

O: [
down
O1: ellipse "pipe"
move 0.2
O2: ellipse "smtp"
move 0.2
O3: ellipse "..."
]

arrow from I.I1.e to QI.w
arrow from I.I2.e to QI.w
arrow from I.I3.e to QI.w

arrow from QO.e to O.O1.w
arrow from QO.e to O.O2.w
arrow from QO.e to O.O3.w


line dotted up from SC.n
box invis "external mail scanners" ht 0.2

line dotted down from SC.s
PL: box dashed "message" "pool"
line -> down right from QI.e then to PL.w
line <- down left from QO.w then to PL.e


.PE