Parrot m4 is an incomplete implementation of GNU m4 on top of parrot. As language implementations are encouraged to leave Parrot's svn, I have moved the code and the history over to http://github.com/bschmalhofer/m4. The source can easily be fetched by typing 'make co-m4' in the 'languages' directory of a Parrot working copy.
I am no longer working on m4, so anybody is welcome to clone it. However I think that porting GNU m4 to Perl 6 would be the more interesting task these days.
The mostly up-to-date list of Parrot HLLs is at
