If you like to follow the current source, you should get the source
from this temporary location:
http://nirs.freeshell.org/code/jnext-dev
If you like to contribute to the project, you should install bazaar
<http://bazaar-vcs.org/> and get the source using:
bzr get http://nirs.freeshell.org/code/jnext-dev
http://nirs.freeshell.org/code/jnext-dev