me@unassigned:~# jruby --ng-server
NGServer started on all interfaces, port 2113.
java.net.BindException: Address already in use
        at java.net.PlainSocketImpl.socketBind(Native Method)
        at java.net.PlainSocketImpl.bind(PlainSocketImpl.java:359)
        at java.net.ServerSocket.bind(ServerSocket.java:319)
        at java.net.ServerSocket.<init>(ServerSocket.java:185)
        at java.net.ServerSocket.<init>(ServerSocket.java:97)
        at com.martiansoftware.nailgun.NGServer.run(Unknown Source)
        at java.lang.Thread.run(Thread.java:595)
com.martiansoftware.nailgun.builtins.NGAlias: 0/0
com.martiansoftware.nailgun.builtins.NGClasspath: 0/0
com.martiansoftware.nailgun.builtins.NGServerStats: 0/0
com.martiansoftware.nailgun.builtins.NGStop: 0/0
com.martiansoftware.nailgun.builtins.NGVersion: 0/0
NGServer shut down.