I have not followed this newsgroup for a while. Coco was already ported to
Modula-3 and some time ago I lifted some of the restrictions (number of
symbols etc.) in a CVS branch:
http://modula3.elegosoft.com/cgi-bin/cvsweb.cgi/pm3/m3/pm3/language/parsing/m3coco/
(I compiled it with cm3.)
There is also the Caltech parser, which I have not used so far.