gcl (lisp) break broken?



trying to reproduce David Touretzky's (Common Lisp)
example (p. 272: Lisp Toolkit: The Debugger), but get
a Lisp error (w/ Window's gcl maxima binary):
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(%i1) to_lisp();
Type (to-maxima) to restart, ($quit) to quit Maxima.

MAXIMA> (defun fact (n)
                         (cond ((zerop n) 1)
                        (t (* n (fact (- n 1))))))

FACT
MAXIMA> (fact 5)

120
MAXIMA> (defun fact (n)
                          (cond ((zerop n) (break "N is zero."))
                         (t (* n (fact (- n 1))))))

FACT
MAXIMA> (fact 5)

Maxima encountered a Lisp error:

 N is zero.

Automatically continuing.
To reenable the Lisp debugger set *debugger-hook* to nil.
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Is this a syntax problem or a lisp version problem
or a Windows binary problem?

Ted Woollett