on-value-changed event is not working for multivaluefield

[Papaji Elaprolu]

Hi
on-value-changed event is not working for multivaluefield
<fd:multivaluefield id="dsdepartments">
          <fd:label><i18n:text>Departments</i18n:text></fd:label>
          <fd:datatype base = "string"/>
          <fd:selection-list   src="cocoon:/dynamicStagingDepartmentList" 
dynamic="true" />
<fd:on-value-changed>
            <javascript>
                  I am writing my javascript code here
            </javascript>
 </fd:on-value-changed>
</fd:multivaluefield>

Please help me in this

Thanks in advance
Papaji