diff --git a/src/tags.lisp b/src/tags.lisp
index dd2d5ae..0c78d16 100644
--- a/src/tags.lisp
+++ b/src/tags.lisp
@@ -677,7 +677,7 @@ are prepended to *TEMPLATE-ARGUMENTS*"
               (handler-case
                   (princ (funcall fn) stream)
                 (error (e)
-                  (template-error* e "There was an error executing the lisp form: ~A" sexp))))))
+                  (template-error* e "There was an error executing the lisp form: ~s" sexp))))))
     (error (e)
       (template-error* e "There was an error executing the lisp form ~A" sexp))))