[racket] Stateless Webserver

Hello,

I am going over the Blog Tutorial (
http://docs.racket-lang.org/continue/index.html ) and trying to run it
"Stateless".

I made it to the version where the model is put into a separate module
model.rkt with small changes:

(require racket/serialize)

(serializable-struct  blog (posts) #:mutable)

(serializable-struct post (title body comments) #:mutable)

But when I try out model-2.rkt and model-3.rkt, I run into some trouble.

1) With model-2.rkt, #:prefab seems to be in conflict with
serializable-struct. I get the following error msg:

;; serializable-struct: cannot use #:property specification for prefab
structure type in: #:property

Without #:prefab, however, the model is changed (ie changes are
visible) but nothing is written to .db file.

2) With model-3.rkt, I get a different error msg:

;; stuff-url: Cannot stuff (kont
#<procedure:...abort-resume.rkt:145:3>) into a URL
;; because it contains non-serializable pieces.
;; Convert (object:connection% ...) to a serializable struct

How can I overcome these?

Regards,

jGc