Forum OpenACS Q&A: Mailing List and acs-mail-lite
I've also been trying to CVS checkout mailing-list, which I haven't been able to find either.
I think you want the non-contrib version, though it seems to be 0.2 not 0.3.
This is odd because I have an acs-mail-lite version 0.3 installed on one of my production systems.
I guess my advice is try 0.2 and see if it works. I am pretty sure 0.1 from contrib will not work.