Jme's physics stuff is a higher level of abstraction than odejava.
the creation of GeomTriMesh for terrain/static is automatic, creation of compounded objects of any kind (either static or dynamic) is also automatic.
Different gravity modes are available. E.g. point gravity (think black hole), normal gravity (earth), and planet gravity (simulates gravity between planets).
jme-physics' API is more geared towards the user, how easy it is to get something up and running quickly and easily while still maintaining all the complexities if needed.
Look at a couple of the tests in our respiratory
to see what i mean.