[plt-scheme] Bug in interaction between shared and class system?

#lang scheme

(define Node%
  (class object%
    (init-field value
                next)

    (super-new)))

(define cycle
  (shared ([the-node (new Node% [value "abc"] [next the-node])])
    the-node))
------------------------
If I'm using shared correctly, that should create a Node% that refers
back to itself.

cycle really is a Node%:

> cycle
#(struct:object:Node% ...)

but its next didn't get set correctly.

> (get-field next cycle)
#<undefined>

Is this a bug, or am I not allowed to do this?
Todd