--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/input/mail-agents.pic	Wed Jul 11 15:51:28 2012 +0200
@@ -0,0 +1,66 @@
+.PS 3.5
+arrowhead = 18
+
+define disk {
+Disk: [
+	ellipsewid=ellipsewid/2
+	ellipseht=ellipseht/2
+	ellipse
+	spline down ellipseht*4/3 from last ellipse.w \
+		then right ellipsewid \
+		then up ellipseht*4/3 to last ellipse.e
+]
+}
+
+define machine {
+	box wid $1.wid+.3 ht $1.ht+.3 dashed at $1
+}
+
+up
+Sender: [
+ellipse "\fBMUA\fP"
+ellipse "MSA"
+]
+machine(Sender)
+
+arrow 3*linewid from Sender.n
+
+right
+Server1: [
+ellipse "MTA"
+] with .s at last arrow.end
+machine(Server1)
+
+arrow 2*linewid from Server1.e
+box invis ". . ."
+arrow 2*linewid
+
+Server2: [
+ellipse "MTA"
+ellipse "MDA"
+arrow linewid/2
+disk
+move to Disk.s - (0,.05)
+]
+machine(Server2)
+
+down
+arrow <- 3*linewid dashed from Server2.s+(.86,0)
+arrow 3*linewid from Server2.s+(.9,0)
+
+Recipient: [
+ellipse "MRA"
+ellipse "MDA"
+move to last ellipse.w
+left
+arrow linewid/2
+disk
+arrow <-> linewid/2
+#arrow <-> linewid/2 from Disk.w+(0,.03)
+#arrow linewid/2 from Disk.w+(0,-.03)
+ellipse "\fBMUA\fP"
+] with .n at last arrow.end-(.8,0)
+machine(Recipient)
+
+line from .5 <Sender.nw,Server1.sw> to .5 <Server2.se,Recipient.ne> dotted
+.PE