Richfaces - <rich:Editor> inside jQuery ui dialog

I use a <rich:editor> inside a JQuery UI dialog:

    <div id="helpDialog" style="displa开发者_如何学Cy: none" title="#{messages.help}">
    <rich:editor id="helpTextArea" theme="advanced" value="#{helpUtils.test(helpId)}">
      <f:param name="theme_advanced_buttons1" value="bold,italic,underline,strikethrough,|,justifyleft,justifycenter,justifyright,justifyfull,|,fontselect,fontsizeselect,|,forecolor,backcolor"/>
      <f:param name="theme_advanced_buttons2" value=""/>
      <f:param name="theme_advanced_buttons3" value=""/>
      <f:param name="theme_advanced_toolbar_location" value="top"/>
      <f:param name="width" value="90%"/>
      <f:param name="theme_advanced_toolbar_align" value="left"/>
    </rich:editor>

    <p>
      <button id="editHelpButton">#{messages.edit}</button>
      <button id="saveHelpButton">#{messages.save}</button>
    </p>
</div>

When I click on "font family" or "font size" the dropdown box is shown in the upper left corner of the screen and not inside the dialog. (see screenshot) How can I fix this?

screenshot

Try to put to relative div (<div style="position:relative"/>) inside #helpDialog

Hope it helps. Alexey.