[plt-scheme] MrEd's stdio REPL with GUI code

Consider this simple MrEd program:

;;;;;;;;; /tmp/test-mred.scm ;;;;;;;;;;

(define *frame*
  (make-object frame% "Testing MrEd" #f #f #f #f #f '()))

(define	*text-field*
  (make-object	text-field% #f *frame* (lambda (a b) #t) "" '(single)))

(send *frame* show #t)

;;;;;;;;;; end of file ;;;;;;;;;;

If you first start MrEd:

	$ mred

and load that file at the graphical REPL:

	> (load "/tmp/test-mred.scm")

the window appears and you can type into the text-field. You can also
continue to work in the REPL.

However, if you start MrEd and opt for the stdio REPL:

	$ mred -z

and then load the file, the window appears but it is seemingly
nonresponsive. The stdio REPL continues to respond however.

I've tried this in 103p1 and 201.

Anyone know how to get around this problem? Specifically, I'd like to run
mred, load a file which does some gui stuff, and still interact with mred
via the stdio REPL.

Ed