some more facts :the described behavior only happens inside a datatable. the same construct outside the table, everything runs fine.
<t:dataTable [...] > [...] <h:column> <f:facet name="header"> <t:commandSortHeader columnName="timestamp" arrow="false"> [...] </t:commandSortHeader> </f:facet> <h:outputText value="#{msg.timestamp}" > <f:convertDateTime type="both" dateStyle="medium" timeStyle="full" timeZone="#{config.timeZone}" /> </h:outputText> </h:column> </t:dataTable> regards Ronald