$(document).ready(function() {
    $('#dealer').validate({
        rules: {
            name: {
              required: true
            },
            plz: {
              required: true,
              digits: true
            },
            ort: {
              required: true
            },
            land: {
              required: true
            },
            email: {
              required: true,
              email: true
            }
        },
        messages: {
            name: "",
            plz: "",
            ort: "",
            land: "",
            email: ""
        },
        errorClass: 'invalidate',
        validClass: ''
    });
});