How to exempt element to be validated?

I'm using the validation plugin for jquery: http://docs.jquery.com/Plugins/Validation.

I want to know how would I exempt a field to be validated? Currently all fields inside the form are automatically checked.

I am not sure if this will help since the element that I want to exempt is not included (obviously :) )

  $("#contactForm").validate({
      rules: {
                        first_name:{required: true,charsonly:true,minlength: 1 },
                        last_name:{required:true,char开发者_JAVA百科sonly:true,minlength: 1 },
                        birthday:{required:true,min:1,max:31 },
                        birthmonth:"required",
                        birthyear:"required",
                        username: {required: true,minlength:1,maxlength:32,username:true,notChinese:true,noSpecial:true},
                        password1:{required:true,minlength: 5,maxlength: 10, alphaNum: true },
                        password2:{required:true,minlength: 5,maxlength: 10, alphaNum: true, equalTo: "#password1"},
                        currency:"required",
                        address:{required: true,noSpecial:true,minlength:2},
                        city:{required: true,noSpecial:true,minlength:2},
                        state:{noSpecial:true},
                        countrycode:"required",
                        zip:{required:true,zipTest:true},
                        email:{required:true,email:  true},
                        confirmemail:{required: true,equalTo:  "#email",email:true},
                        phone:{required: true,minlength:6,maxlength:20,phoneUS:true},
                        cellphone:{required: true,minlength:6,maxlength:20,phoneUS:true},
                        custom06:{acceptIM:true}

      } });

Found it. I used the ignore validation method.

Here's the code

$("#myform").validate({
   ignore: ".ignore"
})

It depends on class attribute. See examples:

This field is required and email format: it cannot be empty

input class="required email"

This field is NOT required and email format: it can be empty

input class="email"

This field is NOT required and doesnt have format: it can be empty

input class=""

Are you using some sort of server side technology? The validation library needs to have rules set, and if you are doing this in strictly javaScript (jQuery) it is manual.

UPDATE: You can remove rules with the following: http://docs.jquery.com/Plugins/Validation/rules#.22remove.22rules

Place the following at the end of the body.

$("selector").rules("remove");

You could set your own messages:

$("#contactForm").validate({
      rules: {
         input1: required,
         input2: required,
         no-validation: required,
         input4: required,
      },
      messages: {
         no-validation: ''
      }
});

Just put an empty string for the field you don´t want to show any message for..