Regular Litany of Fatal errors in attempting to follow installing this application

[ASmith-]

~/retroshare-chatserver/trunk$ git submodule update --init
Cloning into '/home/name/retroshare-chatserver/trunk/html'...
Warning: Permanently added the RSA host key for IP address 'xxx.xx.xxx.4' to the list of known hosts.
git@github.com: Permission denied (publickey).
fatal: Could not read from remote repository.
.
Please make sure you have the correct access rights
and the repository exists.
fatal: clone of 'git@github.com:RetroShare/ChatServer.git' into submodule path '/home/name/retroshare-chatserver/trunk/html' failed
Failed to clone 'html'. Retry scheduled
Cloning into '/home/name/retroshare-chatserver/trunk/html'...
git@github.com: Permission denied (publickey).
fatal: Could not read from remote repository.
.
Please make sure you have the correct access rights
and the repository exists.
fatal: clone of 'git@github.com:RetroShare/ChatServer.git' into submodule path '/home/name/retroshare-chatserver/trunk/html' failed
Failed to clone 'html' a second time, aborting
.
Did the author turn-off the lights on supplying the needed files from the remote repository and forget to mention this?