Undefined keys in some layouts #28

What steps will reproduce the problem?
1. Run the command 'setxkbmap latam' or change the keyboard layout to either 
latam or es.
2. Run the following code

(sdl:with-init ()
  (sdl:window 320 240
          :title-caption "Key Test"
          :icon-caption  "Key Test")
  (setf (sdl:frame-rate) 30)

  (sdl:with-events ()
    (:quit-event () t)
    (:video-expose-event () (sdl:update-display))
    (:key-down-event (:key key)
             (format t "Key pressed (~a)~%" key))
    (:idle ()
       (sdl:update-display))))

3. Press '{', '}', '°', '¬', '[' or ']' (and maybe some other keys).

What is the expected output? What do you see instead?

The expected output is, for '{' key: Key pressed (SDL-KEY-LEFTBRACKET)

I get: 123 is not defined as a value for enum type #<CFFI::FOREIGN-ENUM 
LISPBUILDER-SDL-CFFI::SDL-KEY>.
   [Condition of type SIMPLE-ERROR]

Code varies according to the pressed key (123, 124, 125 ...).

What version of the product are you using? On what operating system?

lispbuilder-20110619-svn, as provided by quicklisp.
Using SBCL 1.0.52, slackware linux 13.37 x86_64

Please provide any additional information below.

If I set the keyboard map to 'us' the keys are processed successfully.