Using umbraco v 4.5.1 (Assembly version: 1.0.3858.40498)

I have created a custom section on the Umbraco dashboard and added pages with the necessary functionality.  That's gone fine.

I have a page that allows the user to edit data.  When the user clicks the save button, I want the speech bubble to come up just like it does on the native Umbraco pages.  It isn't coming up for me.  Here's the event that should be triggering it.

protected void btnSave_Click(object sender, EventArgs e)
 {
      // Save the data here... which is working fine so I know the event is firing
      UmbracoEnsuredPage.Current.ClientTools.ShowSpeechBubble(UmbracoEnsuredPage.speechBubbleIcon.success, "Title Text", "Message Text");
 } 

The speech bubble isn't coming up.  I have tried this on a standalone page and also a content page using umbraco/masterpages/umbracoPage.Master as the master.  The content page inherits UmbracoEnsuredPage.  Am I missing something here?  I've even made explicit references to the UmbracoSpeechBubble js files.  Do I need to put something on my .aspx page as a placeholder?