Java Remote desktop toolTag(s): Open Source
Java Remote Desktop Protocol (RDP) Client is an Open Source Java RDP client for Windows Terminal Server.
It runs on Java 1.1 and up, and works on Linux, Windows, Mac and other Java enabled systems. http://www.elusiva.com/opensource/
Simply pass the machine name to connect to on the command line.
javaw -jar JavaRDP13-1.1.jar some.machine.local
javaw -jar JavaRDP14-1.1.jar
There is a port for OpenVMS called JavaRDP for OpenVMS at http://vmsfree.free.fr/freen/index.php?id=38