Thanks Jörn, In case anyone else is using CAKEPHP here's my code: <form action="/" method="post" id="sendmessage"> <label for="ProjectsContactDescription">Send a message to project team</label> <div id="errorMessageBox"> <label for="data[Projects][contact_description]" class="error">Please enter a message</label> <label for="data[Projects][contact][]" class="error">Please select a developers</label> </div> <textarea name="data[Projects][contact_description]" class="text"></ textarea> <label for="developers">Select developers.</label> <table> <tbody> <tr> <td><input id="developer1" class="checkbox" type="checkbox" value="email1" name="data[Projects][contact][]"/>Person1</td> <td><input id="developer2" class="checkbox" type="checkbox" value="email2" name="data[Projects][contact][]"/>Person2</td> </tr> </tbody> </table> <button type="submit" class="custom_button" value="Send a message"><img src="/img/btn_send_a_message.gif" alt="Send a message" / ></button> </form>
var container = $("#errorMessageBox"); $("#sendmessage").validate({ errorContainer: container, errorLabelContainer: $("div", container), event: "keyup", rules: { "data[Projects][contact_description]": {required: true}, "data[Projects][contact][]":{required:true, minLength:1} } });