nested formatting commands fails?

[pc@ctt.ctt.bellcore.com (Peter Clitherow)]

I'm having trouble doing something fairly trivial, yet it mysteriously
fails.  I want to format a list inside a filling-output enviroment.  The
Docex said somewhat cryptically that "Most simple combinations of
formatted output macros work inside of one another".  Yet when i try:

(filling-output (stream :fill-column '(72. :character))
  (fresh-line stream)
  (loop repeat 10 do
    (write-string "this is a test of the stuff " stream))
  (indenting-output (stream '(2 :character))
    (fresh-line stream)
    (loop repeat 10 do
      (write-line "more indenting" stream))))

i get

Error: The object #<DW::FILLING-STREAM 1144550> received a :INCREMENT-CURSORPOS
       message, which went unclaimed.
       The rest of the message was (16 0).

is there some reason you shouldn't be able to do this?  some trivial fix
to this code? (i can nest filling-output inside indenting-output fine though)

thanks
pc