var fields = ["users_email", "confirm_users_email", "users_password", "confirm_users_password", "users_name", "users_lastname", "captcha"];
    function checkRegistration() {
            var data = '';
            for (var i = 0; i < fields.length; i++) 
            {
              data += fields[i] + "=" + $('#'+fields[i]).val();  
              if( i != (fields.length - 1) ) data += "&";   
            }            
            $.ajax({
            type: "POST",
            url: "registration", 
            data: data+"&action=check",
            success: function(json){
                var response = eval('(' + json + ')');
                if (response.status == "OK") {
                    $("#registration").append('<input type="hidden" name="submited" value="1">');
                    $('#registration').submit();
                } else {
                    chancgeCaptcha();
                    $('.error').remove();        
                    var messages = response.errMessages;
                    for (var i = 0; i < fields.length; i++) 
                    {
                        var curField = fields[i];
                        if( messages[curField] )
                        {
                            $("#"+curField).after("<div class='error'>" + messages[curField] + "<\/div>");
                        }                    
                    }               
                }            
            }
            });
            return false;
    }

    function chancgeCaptcha(){       
        var src = "captcha/" + parseInt(Math.random()*10000);
        $("#captchaImage").attr("src", src);      
    }