Hi friends
I was watching this nice video created by @shiffman which uses the toxiclibs verlet physics pure java library to create a 3D cloth in Processing.
Read more on his book: Chapter 5. Physics Libraries
The blanket is simulated by connecting a grid of particles with springs.
Thought some one might be interested to provide an integration for jme 
Simply put, the steps should be generating a grid of connected particles out of jme’s mesh vertex data → give the grid to toxiclib → toxiclib will do the simulation on particles → update vertex position on jme mesh. ?
A cloth simulation demo using Verlet integration on Skyrim