<obout:PopupHolder runat="server" id="popupHolder" DefaultAddPolicy="Demand" PopupsZIndex="200000" />
<asp:UpdatePanel ID="updatePanel1" runat="server">
  <ContentTemplate>
    <obout:Editor style="display:none" runat="server" Id="editor" Height="300px"
                                Width="100%" PopupHolderID="popupHolder" />
    <asp:LinkButton ID="LinkButton1" runat="server" Text="Edit content"
                           OnClientClick="myWindow.Open(); return false;" />
    <hr />
    <asp:Label ID="ContentPanel" runat="server" />
    <owd:Window runat="server" ShowMaximizeButton="true" Title="Edit" Overflow="HIDDEN" ID="myWindow"
                        Width="800" Height="550" Left="200" Top="100" VisibleOnLoad="false"
                        OnClientResize="windowResize();" OnClientOpen="windowOpen();"
                        OnClientPreClose="return windowPreClose();"
                        StyleFolder="../window/wdstyles/default" ShowStatusBar="true">
        <asp:LinkButton runat="server" onclick="SubmitClick" Text="Save content" ID="Submit" />
        <asp:LinkButton ID="CancelButton" runat="server" Text="Cancel"  OnClientClick="return cancelPopup();" />
    </owd:Window>
  </ContentTemplate>
</asp:UpdatePanel>
...
<script type="text/javascript" >

  function pageLoad() {
     if (!Obout.Ajax.UI.HTMLEditor.AjaxPopupLoadingInProgress) {
        var editor = $get("<%= editor.ClientID %>");
        var submit = $get("<%= Submit.ClientID %>");
        submit.parentNode.insertBefore(editor, submit);
        editor.style.display = "";
        if (typeof myWindow != "undefined") {
            myWindow.Close();
        }
     }
  }

  function cancelPopup() {
     myWindow.Close();
     return false;
  }

  function windowResize() {
     var container = $get("<%= editor.ClientID%>");
     var submit = $get("<%= Submit.ClientID %>");
     if (submit.parentNode != container.parentNode) return;
     var step = 20;
     var temp;
     var innerTable = container.firstChild;

     while(innerTable.nodeType != 1 || innerTable.tagName.toUpperCase() != "TABLE") {
        innerTable = innerTable.nextSibling;
     }
     while ((temp = IsInScroll(container)) == 0) {
        innerTable.style.height = parseInt(innerTable.style.height) + step + "px";
     }
     innerTable.style.height = parseInt(innerTable.style.height) - temp + "px";
  }

  function IsInScroll(elem) {
     elem = elem.parentNode.parentNode;
     if (elem.clientHeight > 0 && elem.scrollHeight && elem.scrollHeight > 0) {
        if (elem.scrollHeight > elem.clientHeight) {
          return elem.scrollHeight - elem.clientHeight;
        }
     }
     return 0;
  }

  function windowOpen() {
     windowResize();
  }
  function windowPreClose() {
     if (Obout.Ajax.UI.HTMLEditor.DesignPanel.isPopup()) {
        setTimeout(function() { alert("Close Editor's popups!!!"); }, 0);
        return false;
     }
      return true;
  }

</script>