on redelivery, try shared again too

deliverator.go

@@ -68,6 +68,9 @@ func deliverate(goarounds int, username string, rcpt string, msg []byte) {
 			return
 		}
 		inbox = box.In
+		if box.Shared != "" {
+			inbox = box.Shared
+		}
 	}
 	err := PostMsg(keyname, key, inbox, msg)
 	if err != nil {