Only one JME game per JVM possible?

many things in jme use the singleton pattern… for example:

KeyInput.get() …

is it possible to start 2 independent instances of jme (2 different games) in one jvm?

No, it is not.

Not if you use the word "independent".  With some management, you could most likely run two or more games in a jvm, but it would be extra work.