Have you tried it in standalone mode, like the 'purchasing' example?
If it works there, than it's an app server configuration problem.
look at the examples/testcases. There are lots of errors and wrong assumptions in your code/process. (use the code tags btw for good formatting).
There are NO tasks in your process definition, so NO taskinstances if you start the process.
And as jbpmndc states, try it standalone in a unit test first (See Test Driven Development in the docs and sourcecode of jBPM)