script element in scheduler.xml gets NullPointerException

I'm not sure but I believe to remember that it has worked with 1.5.2264-SNAPSHOT-03bcd8ee87ea0cd0b13c8acb5c4e3010c15cdc6a

If I add a script element in the scheduler.xml:

<?xml version="1.0" encoding="iso-8859-1" standalone="no"?>
<?xml-stylesheet type="text/xsl" href="scheduler_documentation.xsl" ?>

<spooler>
  
  <config mail_xslt_stylesheet="config/scheduler_mail.xsl" port="4464">

    <params>
			<param name="SCHEDULER_VARIABLE_NAME_PREFIX" value="SCHEDULER_PARAM_"/>
			<param name="scheduler.order.keep_order_content_on_reschedule" value="false"/>    
    </params>
    
    
    <security ignore_unknown_hosts="yes">
      <allowed_host host="localhost" level="all"/>
    </security>
    
    
    <plugins>
      <plugin java_class="com.sos.scheduler.engine.plugins.jetty.JettyPlugin">
        <plugin.config/>
      </plugin>
    </plugins>
    
    
    <process_classes>
      <process_class max_processes="30"/>
      <process_class max_processes="10" name="single"/>
      <process_class max_processes="10" name="multi"/>
    </process_classes>
    
    
    <script language="javascript">
			<![CDATA[
				function spooler_init() {
					spooler.variables.set_var( "foo", "bar" );
                                        return true;
				}
			]]>
    </script>

    
    <http_server>
      <http_directory path="${SCHEDULER_HOME}/" url_path="/scheduler_home/"/>
      <http_directory path="${SCHEDULER_DATA}/" url_path="/scheduler_data/"/>
    </http_server>
    
    
    
  </config>

then I get the following error in the scheduler.log

.23 14:22:38.043 scheduler 0 2128.24D0 1293.391MB .

Unknown macro: {scheduler}

Scheduler_script_subsystem: switch_subsystem_state active
.23 14:22:38.043 scheduler 0 2128.24D0 1293.391MB ...

[debug3] (Scheduler_script scheduler) spooler_init()
.23 14:22:38.043 scheduler 0 2128.24D0 1293.391MB ...

Unknown macro: {scheduler.call}

Java_module_instance.spooler_init() begin
.23 14:22:38.047 scheduler 0 2128.24D0 1293.391MB ...

Java_module_instance.spooler_init() end
.23 14:22:38.048 scheduler 16 2128.24D0 1293.391MB ..

Unknown macro: {java.stackTrace}

java.lang.NullPointerException: null value in entry: spooler_task=null
.23 14:22:38.048 scheduler 0 2128.24D0 1293.391MB .. at com.google.common.base.Preconditions.checkNotNull(Preconditions.java:235)
.23 14:22:38.048 scheduler 0 2128.24D0 1293.391MB .. at com.google.common.collect.ImmutableMap.entryOf(ImmutableMap.java:144)
.23 14:22:38.048 scheduler 0 2128.24D0 1293.391MB .. at com.google.common.collect.ImmutableMap.of(ImmutableMap.java:110)
.23 14:22:38.048 scheduler 0 2128.24D0 1293.391MB .. at sos.spooler.jobs.ScriptAdapterJob$1.compute(ScriptAdapterJob.java:26)
.23 14:22:38.048 scheduler 0 2128.24D0 1293.391MB .. at sos.spooler.jobs.ScriptAdapterJob$1.compute(ScriptAdapterJob.java:24)
.23 14:22:38.048 scheduler 0 2128.24D0 1293.391MB .. at com.sos.scheduler.engine.common.Lazy.get(Lazy.java:12)
.23 14:22:38.048 scheduler 0 2128.24D0 1293.391MB .. at com.sos.scheduler.engine.jobapi.scripting.ScriptInstance.loadScript(ScriptInstance.java:66)
.23 14:22:38.048 scheduler 0 2128.24D0 1293.391MB .. at com.sos.scheduler.engine.jobapi.scripting.JobScriptInstanceAdapter.loadScript(JobScriptInstanceAdapter.java:71)
.23 14:22:38.048 scheduler 0 2128.24D0 1293.391MB .. at com.sos.scheduler.engine.jobapi.scripting.JobScriptInstanceAdapter.callInit(JobScriptInstanceAdapter.java:17)
.23 14:22:38.048 scheduler 0 2128.24D0 1293.391MB .. at sos.spooler.jobs.ScriptAdapterJob.spooler_init(ScriptAdapterJob.java:48)
.23 14:22:38.048 scheduler 0 2128.24D0 1293.391MB ..
.23 14:22:38.049 scheduler 0 2128.24D0 1293.391MB ..[xc.insert 1, "java.lang.NullPointerException"]
.23 14:22:38.049 scheduler 0 2128.24D0 1293.391MB ..[xc.insert 2, "null value in entry: spooler_task=null"]
.23 14:22:38.049 scheduler 0 2128.24D0 1293.391MB ..[xc.insert 3, "spooler_init()Z"]
.23 14:22:38.049 scheduler 0 2128.24D0 1293.391MB ..

Unknown macro: {scheduler}

[ERROR] (Scheduler_script scheduler) Z-JAVA-105 Java exception java.lang.NullPointerException("null value in entry: spooler_task=null"), method=spooler_init()Z []
.23 14:22:38.049 scheduler 0 2128.24D0 1293.391MB ..

Scheduler_script_subsystem: state=active