Another piece of info that makes me look - shocked: 1. I loaded the cl-opengl OpenGL bindings from common-lisp.net once again. 2. I just started my lisp process and loaded the cl-opengl package via ASDF 3. A simple (gl:get-error) results in exactly the same error - but no other package is loaded, so I am assuming cl-opengl is not the root cause of this. Hmpf. Another piece: Warning: foreign ARG type :CHAR not compatible with lisp type (INTEGER -128 127) Warning: foreign ARG type :UNSIGNED-CHAR not compatible with lisp type (INTEGER 0 255) I get these warnings and ignored them so far. I seem to remember that I haven't seen these with older versions of AllegroCL and CFFI. AllegroCL is version 8.1 with up-to-date patches. CFFI is latest version from darcs. ??? Cheers Frank -- Frank Goenninger Cell: +49 175 4321058 E-Mail: frgo@me.com