I found my error ... It was a not a jPBM issue since I tried to cast the variable id_element as a String while it was set as a Long ... So it throwed a ClassCastException ... Shame on me ... Moreover the EL expression could be simpler : <action class="fr.xxx.workflow.actions.absences.ValiderDemandeAbsenceAction"> | <idDemande>#{id_element}</idDemande> | </action> | View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4053073#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...