EDIT

this happened in test database:

1. create new registration for "Infusionsthierchen. 1838"
2. new registration for existing name "Trachelomonas Ehrenb." --> causes LazyInitializationException

org.hibernate.LazyInitializationException: failed to lazily initialize a collection of role: eu.etaxonomy.cdm.model.name.Registration.blockedBy, could not initialize proxy - no Session
    at org.hibernate.collection.internal.AbstractPersistentCollection.throwLazyInitializationException(AbstractPersistentCollection.java:567)
    at org.hibernate.collection.internal.AbstractPersistentCollection.withTemporarySessionIfNeeded(AbstractPersistentCollection.java:205)
    at org.hibernate.collection.internal.AbstractPersistentCollection.readSize(AbstractPersistentCollection.java:146)
    at org.hibernate.collection.internal.PersistentSet.isEmpty(PersistentSet.java:149)
    at eu.etaxonomy.cdm.vaadin.view.registration.RegistrationDTO.isBlocked(RegistrationDTO.java:363)
    at eu.etaxonomy.cdm.vaadin.view.registration.RegistrationWorksetViewBean.putRegistrationListComponent(RegistrationWorksetViewBean.java:326)
    at eu.etaxonomy.cdm.vaadin.view.registration.RegistrationWorksetViewBean.createRegistrationsList(RegistrationWorksetViewBean.java:227)
    at eu.etaxonomy.cdm.vaadin.view.registration.RegistrationWorksetViewBean.setWorkingset(RegistrationWorksetViewBean.java:171)
    at eu.etaxonomy.cdm.vaadin.view.registration.RegistrationWorkingsetPresenter.onRegistrationWorkflowEventActionStart(RegistrationWorkingsetPresenter.java:432)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.vaadin.spring.events.internal.MethodListenerWrapper.publish(MethodListenerWrapper.java:78)
    at org.vaadin.spring.events.internal.ListenerCollection.publish(ListenerCollection.java:167)
    at org.vaadin.spring.events.internal.ScopedEventBus.publish(ScopedEventBus.java:116)
    at org.vaadin.spring.events.internal.ScopedEventBus.publish(ScopedEventBus.java:109)
    at eu.etaxonomy.cdm.vaadin.view.registration.RegistrationWorksetViewBean.lambda$1(RegistrationWorksetViewBean.java:242)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at com.vaadin.event.ListenerMethod.receiveEvent(ListenerMethod.java:510)
    at com.vaadin.event.EventRouter.fireEvent(EventRouter.java:200)
    at com.vaadin.event.EventRouter.fireEvent(EventRouter.java:163)
    at com.vaadin.server.AbstractClientConnector.fireEvent(AbstractClientConnector.java:1015)
    at com.vaadin.ui.Button.fireClick(Button.java:377)
    at com.vaadin.ui.Button$1.click(Button.java:54)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at com.vaadin.server.ServerRpcManager.applyInvocation(ServerRpcManager.java:158)
    at com.vaadin.server.ServerRpcManager.applyInvocation(ServerRpcManager.java:119)
    at com.vaadin.server.communication.ServerRpcHandler.handleInvocation(ServerRpcHandler.java:437)
    at com.vaadin.server.communication.ServerRpcHandler.handleInvocations(ServerRpcHandler.java:402)
    at com.vaadin.server.communication.ServerRpcHandler.handleRpc(ServerRpcHandler.java:273)
    at com.vaadin.server.communication.UidlRequestHandler.synchronizedHandleRequest(UidlRequestHandler.java:90)
    at com.vaadin.server.SynchronizedRequestHandler.handleRequest(SynchronizedRequestHandler.java:41)
    at com.vaadin.server.VaadinService.handleRequest(VaadinService.java:1436)
    at com.vaadin.server.VaadinServlet.service(VaadinServlet.java:380)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)
    at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:841)
    at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1634)