clackup app with woo got "message-complete callback failed", but succeeded with woo:run

[WildBench]

Can anyone help with my trouble?
The test app is as followed. It failed with clackup with woo, but went through with woo:run, clackup also worked with hunchentoot.

SBCL 2.4.11
woo 20241012-git
clack 20241012-git
hunchentoot-1.3.1

(dolist (p '(:clack :cl-who :lack-request :woo))
  (ql:quickload p))

(defun demo (env)
  (declare (ignore env))
  (case (getf env :request-method)
    (:get
     `(200 nil (,(cl-who:with-html-output-to-string (s)
		   (:html
		    (:body
		     (:form :method "post" 
			    :enctype "multipart/form-data"
			    (:input :type "text"
				    :name "foo")
			    (:input :type "text" :name "bar")
			    (:input :type "submit"))))))))
    (:post
     (let* ((req (lack.request:make-request env))
	    (foo (assoc "foo" (lack.request:request-body-parameters req) :test #'equal))
	    (bar (assoc "bar" (lack.request:request-body-parameters req) :test #'equal))
	    )
       `(200 nil (,(format nil "~S~%~S~%~S~%" env foo bar)))))))

(defparameter *handler* (clack:clackup 'demo :server :woo))
;(woo:run 'demo)

The error was:
Callback Error: the message-complete callback failed
#<CIRCULAR-STREAMS:CIRCULAR-INPUT-STREAM {1011889533}> cannot be printed readably.