diff --git a/new-server.rkt b/new-server.rkt
index 7a82f6a..db268b6 100644
--- a/new-server.rkt
+++ b/new-server.rkt
@@ -7,6 +7,7 @@
 (require "ssh-numbers.rkt")
 (require "ssh-transport.rkt")
 (require "ssh-session.rkt")
+(require "ssh-channel.rkt")
 (require "ssh-message-types.rkt")
 (require "ssh-exceptions.rkt")
 (require "os2-support.rkt")
@@ -25,8 +26,67 @@
 	   peer-identification-string)))
 
 (define (repl-boot self-pid)
-  (write 'repl-boot) (newline) (flush-output)
-  'no-repl-state)
+  (transition 'no-repl-state
+    (role 'spy (or (topic-subscriber (wild) #:virtual? #t)
+		   (topic-publisher (wild) #:virtual? #t))
+      #:state state
+      [message
+       (write `(APP ,message))
+       (newline)
+       (flush-output)
+       state])
+    (at-meta-level
+     (role 'channel-listener (topic-subscriber (channel-message (channel-stream-name #t (wild))
+							       (wild)))
+       #:state state
+       #:topic t
+       #:on-presence
+       (if (topic-virtual? t)
+	   state
+	   (match t
+	     [(topic _ (channel-message (channel-stream-name _ cname) _) _)
+	      (transition state (spawn (repl-instance cname) #:debug-name cname))]))))))
+
+(define (repl-instance cname)
+  (define inbound-stream (channel-stream-name #t cname))
+  (define outbound-stream (channel-stream-name #f cname))
+  (define (handle-channel-message state body)
+    (match body
+      [(channel-stream-request #"pty-req" _)
+       (transition state
+	 (at-meta-level (send-message (channel-message inbound-stream (channel-stream-ok))
+				      'subscriber)))]
+      [m
+       (write `(channel inbound ,m)) (newline)
+       state]))
+  (match (channel-name-type cname)
+    [#"session"
+     (transition 'no-instance-state
+       (at-meta-level
+	(role 'input (topic-subscriber (channel-message inbound-stream (wild)))
+	  #:state state
+	  #:on-presence (transition state (at-meta-level
+					   (send-message
+					    (channel-message inbound-stream
+							     (channel-stream-config
+							      (default-packet-limit)
+							      #""))
+					    'subscriber)))
+	  [(channel-message _ body)
+	   (handle-channel-message state body)]))
+       (at-meta-level
+	(role 'output (topic-publisher (channel-message outbound-stream (wild)))
+	  #:state state
+	  [m
+	   (write `(channel outbound ,cname ,m)) (newline)
+	   state])))]
+    [type
+     (transition 'no-instance-state
+       (at-meta-level (send-message
+		       (channel-message outbound-stream
+					(channel-stream-open-failure
+					 SSH_OPEN_UNKNOWN_CHANNEL_TYPE
+					 (bytes-append #"Unknown channel type " type))))))]))
 
 (define (connection-handler local-addr remote-addr)
   (define local-identification #"SSH-2.0-RacketSSH_0.0")
@@ -113,7 +173,7 @@
  (transition 'no-state
    (spawn (timer-driver 'timer-driver))
    (spawn tcp-driver #:debug-name 'tcp-driver)
-   ;;(spawn tcp-spy #:debug-name 'tcp-spy)
+   (spawn tcp-spy #:debug-name 'tcp-spy)
 
    (spawn (transition 'no-state
 	    (role 'connection-waiter (topic-subscriber (tcp-channel (wild) server-addr (wild))
diff --git a/ssh-session.rkt b/ssh-session.rkt
index ef4ab0a..226a523 100644
--- a/ssh-session.rkt
+++ b/ssh-session.rkt
@@ -630,13 +630,13 @@
 	     (! conn (ssh-msg-channel-open (channel-name-type cname)
 					   (ssh-channel-local-ref ch)
 					   0
-					   (default-packet-limit)
+					   maximum-packet-size
 					   extra-data))
 	     ;; This must be intended to form the SSH_MSG_CHANNEL_OPEN_CONFIRMATION.
 	     (! conn (ssh-msg-channel-open-confirmation remote-ref
 							(ssh-channel-local-ref ch)
 							0
-							(default-packet-limit)
+							maximum-packet-size
 							extra-data)))]
 	[(channel-stream-credit count)
 	 (! conn (ssh-msg-channel-window-adjust remote-ref count))]