Calendar's skin does not take CssClass?

Hi,

I've been styling controls like GridView, Buttons, Labels, etc. using themes
(i.e. skin and css files). No issues with the above controls.

I'm not able to use CssClass within a skin for the Calendar control. For
example, the following works fine:
<asp:Calendar runat="server" BackColor="White" BorderColor="#b5c667"
BorderWidth="1px">

<TitleStyle BackColor="#b5c667" ForeColor="#ffffff" Font-Bold="True" />

<NextPrevStyle BackColor="#b5c667" ForeColor="#ffffff" Font-Bold="True" />

<DayStyle ForeColor="#336dcc" />

<TodayDayStyle BackColor="#eaf6fd" ForeColor="#336dcc"/>

<SelectedDayStyle BackColor="#ffe6a1" ForeColor="#336dcc" Font-Bold="True"
/>

</asp:Calendar>


.... but this does not:
Skin file:

<asp:Calendar runat="server" CssClass="cal">

<TitleStyle CssClass="calTitle" />

<DayStyle CssClass="calDay" />

<TodayDayStyle CssClass="calTodayDay" />

<SelectedDayStyle CssClass="calSelDay" />

</asp:Calendar>

Css file:

..cal

{

background-color: #ffffff;

}

..calTitle

{

background-color: #d1e07b;

}

..calDay

{

color: Blue;

}

..calTodayDay

{

background-color: #eaf6fd;

}

..calSelDay

{

background-color: #ff0000;

}


Is this a known thing?

Thanks,
Bogdan