问jQuery对话框引发错误

EN

(this.uiDialogTitlebarCloseText = c("<span/>")).addClass("ui-icon ui-icon-closethick").text(m.closeText).appendTo is not a function

// Javascript code from custom_plugin.js
jQuery(document).ready(function() {
  jQuery('#dialog').dialog();
});  

// Code from my custom_plugin.php
<div class="icon32" id="icon-tools"><br></div>
<h2>Gallery manager</h2>

<div id="poststuff" class="metabox-holder">
  <div id="post-body">
    <div id="post-body-content">
      <div id="dialog" title="File browser"> This is a dialog.</div>                               
    </div>
  </div>       
</div>

  jQuery("#fileBrowser").dialog({
        title: "File browser",
        modal: true,
        autoOpen: false,
        height: 700,
        width: 800,
        open: function() {
          jQuery("#fileBrowser").load("../wp-content/plugins/wp-filebrowser/fileBrowser.php", function() {

            // Clear input / feedback text when entering new folder name
            jQuery('#newDirDialog input[type=text]').focus(function() {
              jQuery(this).val('');
              jQuery('.newDirFedback').fadeOut(function(){ jQuery(this).empty(); });
            });

            // Initialize create new dir dialog window
              jQuery("#newDirDialog").dialog({ 
                autoOpen: false, modal: true, title: "New dir"
              });
          });
        }
      }
  ); 

  //Open dialog box on click from WP admin         
  jQuery('.addImage').click(function() {
    imageUrlInputBox = jQuery(this).siblings(":text");
    imagePreviewLink = jQuery(this).siblings("a");
    jQuery("#fileBrowser").dialog("open");
  });