The value of the rendered attribute is not interpreted in the column element inside a headerRow element. The outputText.rendered attribute is interpreted correctly in the following example, but the column.rendered attribute has no influence. There is an empty table cell when running this example.

                        <ice:headerRow>
                            <ice:column colspan="2" rendered="false">
                                <ice:outputText value="#{i18n.messages['QueryResultEvent']}" rendered="false"/>
                            </ice:column>
                        </ice:headerRow>

It works correctly if the column element is not inside a headerRow element.