Problem with Ajax Request

Hello.
Iám using CK Editor 3.0.1 And submit my Form with an Ajax Request.

$(document).ready(function(){
    $('#create_a_post').submit(function(){
        action = $(this).attr('action');
        $('#post_menue1').addClass('loading');
        $.post(action,$("#create_a_post").serialize(),function(data){

            var answer = data.split("|");
            if(answer[0]=='error'){
                $('#note').html('Fehler beim speichern');
                $('#post_menue1').removeClass('loading');
            }
            else if(answer[0]=='ok') {
                $('#post_menue1').html(answer[2]);
                $('#do').attr('value', answer[3]);
                $('#post_menue1').removeClass('loading');
            }
            else {
                $('#note').html(data);
                $('#post_menue1').removeClass('loading');
            }
      });
  return false;
    });
});

But the CK-Editor send "Write your Comment." at $_POST['editor1'].

When i Save it again, then i get my content. Why?
And please forgive me my bad english^^