jQuery Grid Plugin - jqGrid

I add one field to the form like this:

 onInitializeForm: function (formid)
                {
                    var cppass = '<tr id="tr_password" class="FormData" rowpos="4">';
                    cppass += '<td class="CaptionTD ui-widget-content">Mot de passe</td>';
                    cppass += '<td class="DataTD ui-widget-content" style="white-space: pre;">';
                    cppass += ' <input id="password" class="FormElement" type="password" name="password" size="20"/>';
                    cppass += '</td></tr>';
                    $(cppass).insertAfter("#tr_debug",formid);
                },

I would like to attribute this property:

editrules:{required:true}

Is it possible even if the field is not in colModel ?