RS delete an efficient statement in home

2016-12-27 15:37:07,635 [ajp-nio2-8068-exec-4] ERROR OLATRuntimeException - OLAT::ERROR ^%^ N68-E13 ^%^ org.olat.core.logging 

https://xyz.openolat.com/auth/HomeSite/196611/effstatements/0
Mozilla/5.0 (Windows NT 6.1; WOW64; rv:50.0) Gecko/20100101 Firefox/50.0
**RedScreen** attempt to create delete event with null entity

<dispatchinfo>
	<componentinfo>
		<compname>link_0</compname>
		<compclass>org.olat.core.gui.components.link.Link</compclass>
		<extendedinfo>n/a</extendedinfo>
		<event>
			<class>org.olat.core.gui.control.Event</class>
			<command>link_0</command>
			<tostring>com:link_0,org.olat.core.gui.control.Event@be46a54a</tostring>
		</event>
	</componentinfo>
	<controllerinfo>
		<controllername>org.olat.core.gui.control.generic.modal.DialogBoxController</controllername>
		<controllername>org.olat.course.certificate.ui.CertificateAndEfficiencyStatementListController</controllername>
		<controllername>org.olat.home.HomeMainController</controllername>
		<controllername>org.olat.core.commons.fullWebApp.BaseFullWebappController</controllername>
	</controllerinfo>
</dispatchinfo>

>>> stack of 1.cause::org.olat.core.logging.OLATRuntimeException: attempt to create delete event with null entity
-> at org.olat.core.gui.exception.ExceptionWindowController.<init>(ExceptionWindowController.java:116)
   at org.olat.core.gui.exception.MsgFactory.createMessageChiefController(MsgFactory.java:57)
   at org.olat.core.gui.exception.MsgFactory.createMessageChiefController(MsgFactory.java:46)
   at org.olat.core.gui.components.Window.dispatchRequest(Window.java:547)
   at org.olat.core.gui.components.Window.doDispatchRequest(Window.java:240)
   at org.olat.core.gui.components.AbstractComponent.dispatchRequest(AbstractComponent.java:193)
   at org.olat.dispatcher.AuthenticatedDispatcher.processValidDispatchURI(AuthenticatedDispatcher.java:275)
   at org.olat.dispatcher.AuthenticatedDispatcher.execute(AuthenticatedDispatcher.java:192)
   at org.olat.core.servlets.OpenOLATServlet.executeUserRequest(OpenOLATServlet.java:289)
   at org.olat.core.servlets.OpenOLATServlet.doPost(OpenOLATServlet.java:232)
   at javax.servlet.http.HttpServlet.service(HttpServlet.java:648)
>>> stack of 2.cause::java.lang.IllegalArgumentException: attempt to create delete event with null entity
-> at org.hibernate.event.spi.DeleteEvent.<init>(DeleteEvent.java:48)
   at org.hibernate.internal.SessionImpl.delete(SessionImpl.java:896)
   at org.hibernate.jpa.spi.AbstractEntityManagerImpl.remove(AbstractEntityManagerImpl.java:1214)
   at org.olat.course.assessment.EfficiencyStatementManager.deleteEfficiencyStatement(EfficiencyStatementManager.java:684)
   at org.olat.course.certificate.ui.CertificateAndEfficiencyStatementListController.doDelete(CertificateAndEfficiencyStatementListController.java:304)
   at org.olat.course.certificate.ui.CertificateAndEfficiencyStatementListController.event(CertificateAndEfficiencyStatementListController.java:277)
   at org.olat.core.gui.control.DefaultController$1.run(DefaultController.java:246)
   at org.olat.core.logging.activity.ThreadLocalUserActivityLoggerInstaller.runWithUserActivityLogger(ThreadLocalUserActivityLoggerInstaller.java:108)
   at org.olat.core.gui.control.DefaultController.dispatchEvent(DefaultController.java:243)
   at org.olat.core.gui.control.DefaultController.fireEvent(DefaultController.java:190)
   at org.olat.core.gui.control.generic.modal.DialogBoxController.event(DialogBoxController.java:205)