This functionality is supported only if you are using the Open Agent.
Applications that start using the Java Network Launching Protocol (JNLP) require additional configuration in Silk Test Classic. Because these applications are started from the Web, you must manually configure the application configuration to start the actual application as well as the application that launches the "Web Start". Otherwise, the test will fail on playback unless the application is already running.
For example, to use the SwingSet3 JNLP application, type const sCmdLine = "%ProgramFiles%\Java\jre6\bin\javaws.exe http://download.java.net/javadesktop/swingset3/SwingSet3.jnlp"
When you replay the test case, the JNLP application starts as expected.