In the current 1.0.7-SNAPSHOT release you need to provide these system properties to make the testing tools connect to run against an already running Sling instance:
Only the first one is really needed, the 2 others are only required to make the creation of the JarExecutor succesfull. If you want to connect only to an instance which is already running, the JarExecutor is not needed at all.
Therefor I would like to get rid of the need to specify the 2 "jar.executor.*" properties. Please see attached patch for a proposal how to achieve it.