Modal font prompting on OS X?

(I haven't had any responses about window-modal print dialogs, and
this is related, so I'm crossing my fingers hoping for a response…)

Is there a way to prompt for a font on OS X that doesn't hold up the
whole application?  The following (with comments) illustrates the
issue:

CL-USER 3 >
(capi:with-dialog-results (result okp)
    (capi:prompt-for-string "enter a string...")
  (print (list result okp)))
:CONTINUATION
NIL
;; the printing occurred in the output buffer as expected.

CL-USER 4 >
(capi:with-dialog-results (result okp)
    (capi:prompt-for-font "select a font...")
  (print (list result okp)))
#S(GRAPHICS-PORTS:FONT :FONT-DESCRIPTION
#S(GRAPHICS-PORTS:FONT-DESCRIPTION :ATTRIBUTES (:NAME "Geneva" :FAMILY
"Geneva" :SIZE 12.0 :WEIGHT :REGULAR :SLANT :ROMAN :PITCH :VARIABLE))
:DEVICE-FONT NIL)
T
;; the printing didn't occur, and the values were returned to the toplevel

Now, I don't see :CONTINUATION in the lambda-list for prompt-for-font,
but the macroexpanded code from with-dialog-results does pass one, and
there's no error signaled about a bad keyword argument.  Of course, it
seems like the results of function-lambda-list don't necessarily align
with what's actually there.  :CONTINUATION isn't shown for
prompt-for-string either, but the documentation does describe it…

All help greatly appreciated.
Thanks in advance,
//JT

-- 
=====================
Joshua Taylor
tayloj@cs.rpi.edu, jtaylor@alum.rpi.edu

"A lot of good things went down one time,
  back in the goodle days."
    John Hartford