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Grammar: http://svn.complang.org/colm/trunk/colm/lmparse.kl

TXL, its apparently predecessor, is very well documented (http://www.txl.ca/). TXL is a very interesting approach to parsing and worth reading up on if you're interested in the area (or are waiting for documentation for Colm :)

There seems to be a PhD thesis behind, so you should check it for the grammar.