ProcessApplicationStartService throws Exception deploying EjbProcessApplication with PostDeploy hook

In my application I have a Custom Processapplication-Bean with PostDeploy-hook:

@Singleton
@Startup
@ConcurrencyManagement(ConcurrencyManagementType.BEAN)
@TransactionAttribute(TransactionAttributeType.REQUIRED)
@ProcessApplication("NeKu Aktiv")
@Local(ProcessApplicationInterface.class)
public class NeukuAktivProcessApplication extends EjbProcessApplication{

@PostConstruct
public void start()

{ deploy(); }

@PreDestroy
public void stop()

{ undeploy(); }

@PostDeploy
public void registerProcessApplication(ProcessEngine processEngine, ProcessApplicationInfo processApplicationInfo) {
// do some magic...
}

@PreUndeploy
public void unregisterProcessApplicaiton(ProcessEngine processEngine) {
for (ProcessApplicationRegistration registration : processApplicationRegistrations)

{ processEngine.getManagementService().unregisterProcessApplication(registration.getDeploymentId(), true); }

}
}

When I try to deploy my application I get the following Exception:

29.07.2013 10:49:23,975 ERROR [org.jboss.msc.service.fail] (MSC service thread 1-1) MSC00001: Failed to start service org.camunda.bpm.platform.process-application-module."deployment.neukuaktiv.war:main".START: org.jboss.msc.service.StartException in service org.camunda.bpm.platform.process-application-module."deployment.neukuaktiv.war:main".START: Exception while invoking the @PostDeploy method
at org.camunda.bpm.container.impl.jboss.service.ProcessApplicationStartService.invokePostDeploy(ProcessApplicationStartService.java:192)
at org.camunda.bpm.container.impl.jboss.service.ProcessApplicationStartService.start(ProcessApplicationStartService.java:133)
at org.jboss.msc.service.ServiceControllerImpl$StartTask.startService(ServiceControllerImpl.java:1811) [jboss-msc-1.0.2.GA.jar:1.0.2.GA]
at org.jboss.msc.service.ServiceControllerImpl$StartTask.run(ServiceControllerImpl.java:1746) [jboss-msc-1.0.2.GA.jar:1.0.2.GA]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) [rt.jar:1.7.0_25]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) [rt.jar:1.7.0_25]
at java.lang.Thread.run(Thread.java:724) [rt.jar:1.7.0_25]
Caused by: java.lang.IllegalArgumentException: object is not an instance of declaring class
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) [rt.jar:1.7.0_25]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) [rt.jar:1.7.0_25]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) [rt.jar:1.7.0_25]
at java.lang.reflect.Method.invoke(Method.java:606) [rt.jar:1.7.0_25]
at org.camunda.bpm.container.impl.jboss.service.ProcessApplicationStartService.invokePostDeploy(ProcessApplicationStartService.java:190)
... 6 more