Slide Show Ajax

I get the below error when I try  to add  SlideShowAnimationType="SlideRight" to the Tag I get this from the http://www.asp.net/AjaxLibrary/AjaxControlToolkitSampleSite/SlideShow/SlideShow.aspx

Type 'AjaxControlToolkit.SlideShowExtender' does not have a public property named 'SlideShowAnimationType'.

here is my code any idea why is this !!

<asp:SlideShowExtender ID="SlideShowExtender1" runat="server"
AutoPlay="true" 
Loop="true" 
SlideShowServiceMethod="GetSlides"
TargetControlID="Image1" ClientIDMode="AutoID" Enabled="True" 
PlayInterval="900" UseContextKey="True" SlideShowAnimationType="SlideRight" ></asp:SlideShowExtender>