I was *grepping* things around inside PicoLisp's sources and I end up
with some permissions errors.
And indeed, some file have a 640 permission mask:
$ ls -l ./lib/el/inferior-picolisp.el
-rw-r----- 1 ice users 13K Dec 28 2009 ./lib/el/inferior-picolisp.el
Also, it was installed in '/opt' instead of '/usr/share', I left a
comment of the related page:
I hope the maintainer will react at some point...