If you are running the BlackBerry JDE 7.0 with the BlackBerry
Java Plug-in v1.5, you
must
launch the Mobile Data System (MDS) manually for the BlackBerry simulator to
run.
MDS is a framework that offers security, wireless
connectivity, manageability options, and development methods. You need it to
run the simulator. It is a known
issue,
which has been fixed in BlackBerry JDE 7.1,
that the simulator cannot launch
MDS.