jpf.jar is not in the host VM classpath, but that is most likely not your only problem since you don't set JPF's 'classpath', i.e. JPF wouldn't find your system under test. Please note that running JPF requires setting two classpaths - one for the host VM to find all the classes (including extensions) that constitute JPF itself ('native_classpath'), and one for the classes that have to be loaded/executed by JPF ('classpath' - your system under test). While you can set this up manually, JPF has a lot of infrastructure to construct these paths from its configuration files (Config, RunJPF etc.). Please see
http://babelfish.arc.nasa.gov/trac/jpf/wiki/user/config for details.
P.S. JPF does not need bcel, make sure you have a recent JPF version
-- Peter