i got a simple class implementing the actionhandler.

but when i try to execute it i got

WaitAndSignal cannot be cast to org.jbpm.graph.def.ActionHandler

code is

import org.jbpm.graph.def.ActionHandler;
import org.jbpm.graph.exe.ExecutionContext;


public class WaitAndSignal implements ActionHandler{

 private final static long serialVersionUID=1l;

 public void execute(ExecutionContext executionContext) throws Exception {
 // TODO Auto-generated method stub
 try {
 System.out.println("Begin WaitAndSignal");
 long dauer = System.currentTimeMillis()% 100000;
 Thread.sleep(dauer);
 executionContext.getProcessInstance().signal();
 System.out.println("pid is = " +executionContext.getProcessInstance().getId() );
 }
 catch(Exception e ) {
 e.printStackTrace();
 }
 System.out.println("end WaitAndSignal");

 }

 int wait =100;

 public int getWait() {
 return wait;
 }

 public void setWait(int wait) {
 this.wait = wait;
 }

}

<?xml version="1.0" encoding="UTF-8"?>

<process-definition xmlns="urn:jbpm.org:jpdl-3.2" name="autokette">


 <start-state name="start-state1">
 <transition to="node1"></transition>
 <event type="node-enter">
 <action name="weiter" class="mypackage.WaitAndSignal" ></action>
 </event>
 </start-state>


 <node name="node1">
 <transition to="node2"></transition>
 <event type="node-enter">
 <action name="weiter" class="mypackage.WaitAndSignal" ></action>
 </event>

 </node>

 <node name="node2">
 <transition to="node3"></transition>
 <event type="node-enter">
 <action name="weiter" class="mypackage.WaitAndSignal" ></action>
 </event>

 </node>

 <node name="node3">
 <transition to="end-state1">
 </transition>
 <event type="node-enter">
 <action name="weiter" class="mypackage.WaitAndSignal" ></action>
 </event>

 </node>


 <end-state name="end-state1"></end-state>


</process-definition>