Java EE (Java Enterprise Edition) General Discussion

hi, kann jemand mich helfen? ich habe fast das selbe Problem wie
http://www.tutorials.de/forum/j2ee/264251-hibernate-collection-mit-list.html

habe eine bidirektionale many-to-one assoziation
employee *-1 division
benutze jsf(myfaces1.1 here nicht so relevant) und hibernate3.1core

in View divisionList.jsp :

<h:column>
        			<f:facet name="header">
        				<h:outputText value="Employees"/>
        			</f:facet>
        			<h:dataTable id="divEmployee" 
        			  			 value="#{division.employees}" 
        			  			 var="employee">
        			  	<h:column>
        			 		<h:outputText value="#{employee.nickname}"></h:outputText>   //fehlerort, kann nickname nicht kennen
						</h:column>
        			</h:dataTable>
				</h:column>

als ich die View aufrufen, kommt die fehlermeldung :

javax.faces.el.PropertyNotFoundException: Bean: org.hibernate.collection.PersistentSet, property: nickname
	org.apache.myfaces.el.PropertyResolverImpl.getPropertyDescriptor(PropertyResolverImpl.java:500)
	org.apache.myfaces.el.PropertyResolverImpl.getPropertyDescriptor(PropertyResolverImpl.java:472)
	org.apache.myfaces.el.PropertyResolverImpl.getProperty(PropertyResolverImpl.java:436)
	org.apache.myfaces.el.PropertyResolverImpl.getValue(PropertyResolverImpl.java:85)
	org.apache.myfaces.el.ELParserHelper$MyPropertySuffix.evaluate(ELParserHelper.java:535)
	org.apache.commons.el.ComplexValue.evaluate(ComplexValue.java:145)
	org.apache.myfaces.el.ValueBindingImpl.getValue(ValueBindingImpl.java:386)
.......................................

------------------------------------------------------------------------------------------------------------------
mapping in Employee.hbm.xml :

<many-to-one name="division" class="....hibernate.Division" fetch="select" lazy="false">
            	<column name="EMP_DIVISION" />
        	</many-to-one>

in Division.hbm.xml :

<set name="employees" inverse="true">
            <key>
                <column name="EMP_DIVISION" />
            </key>
            <one-to-many class=".....hibernate.Employee" />
        </set>

--------------------------------------------------------------------------------------------------------------------
in beans: in Division.java

private Set employees = new HashSet(0);

in employee.java einfach :
private Division division;