not validating with W3C XHTML standards

I just published my website...
www.kevinroseworld.com
and am trying to get the XHTML validated. But I am always getting an error with the calender part of my page. The code I use to produce the calender is...


<asp:Calendar id="calendar" runat="server" BorderWidth="1px"
                            BackColor="#FFFFCC" DayNameFormat="Shortest"
                            Font-Names="Verdana" Font-Size="8pt" ForeColor="#663399"
                            Show ...