For what it's worth, I had the same error: the Could not find or load main class org.codehaus... thing, but without any other info (you'll find many people with this error message - but usually accompanied by extra info such as class loading failures).
It turns out I had a corrupted install, perhaps a some files silently failed to unzip or something. A rm -rf of the maven directory and re-download and unzipped fixed it.
