I found my problem. You just have to know that <f:convertDateTime> works by default with UTC time and not with the date variable timezone, which is not the case with java.util.SimpleDateFormat. So you have to explicitely set the timezone attribute for <f:convertDateTime> Something like that : <h:outputText value="#{membre.dateDebut}"> | <f:convertDateTime pattern="#{messages['datePattern']}" timeZone="GMT+1" /> | </h:outputText> View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4105948#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...