API call job_chain.add_job() fails

<script  language="javax.script:ecmascript">
        <![CDATA[
function spooler_process(){

	var my_job_chain = spooler.create_job_chain();
        my_job_chain.set_name("test");
        my_job_chain.add_job( "/test/job1", "100",  "200", "999" );
        my_job_chain.add_end_state( "200" );
        my_job_chain.add_end_state( "999" );
	return false;
}
        ]]>
    </script>

[Z-JAVA-105  Java exception java.lang.RuntimeException: COM-80020009  Ausnahmefehler aufgetreten. [] [Z-JAVA-105  Java exception java.lang.NullPointerException: startNode, method=CallVoidMethodA [] (Calling Spooler.Job_chain.add_job)], method=spooler_process()Z [], in Remote_module_instance_server::step], method=call