ASP.Net MVC3 Remote Data Annotation Not Working -

i have class data annotations using remote attribute:

public class person  {        [remote("namevalidation","validation", errormessage = "field invalid", fields = "lastname")]     public string firstname { get; set; }     public string lastname { get; set; }  } 

in validationcontroller:

    public actionresult namevalidation(string firstname, string lastname)     {         bool isnamevalid = true;          if (firstname.contains("john") && lastname.contains("doe"))         {             isnamevalid = false;         }          return json(isnamevalid, jsonrequestbehavior.allowget);     } 

in view have:

@{html.enableclientvalidation(); } @using (html.beginform()) {      @html.editorfor(x => x.firstname) @html.validationmessagefor(x => x.firstname)     @html.editorfor(x => x.lastname) @html.validationmessagefor(x => x.lastname)     <input name="finishbutton" type="submit" id="button" > } 

the namevalidation gets called if add required attribute this:

public class person  {        [required]     [remote("namevalidation","validation", errormessage = "field invalid", fields = "lastname")]     public string firstname { get; set; }     public string lastname { get; set; }  } 

how remote validation work without having have required validation?

update mvc3 rc2. tried without required attribute. working. 1 thing found strange though, remote validation fired on every key press , onchange other times