If someone is interested, I managed to install Matlisp on SBCL 0.9.4 OS
X. There seem to be some problems with the help system, like those
described at
http://www.nonperiodic.net/blog/2005/06/19/sbcl-gentoo-installation-diary/
The installation did not work out of the box for me, but some fiddling
with the makefile did the job.
I have g77 (gcc 3.4) and Xcode 2.2.