ASP.NET Panel Control BorderStyle="Outset" Not Working in IE9

I have panel controls in my asp.net webform pages that have their BorderStyle="Outset".   Instead, the border is rendering as solid black.

<asp:Panel ID="pnlControl" runat="server" BackColor="WhiteSmoke" BorderStyle="Outset" Width="300px" Height="200px">
I am running in IE9 with BrowserMode = IE9 and Document Mode = IE9.    If I run with DocumentMode = IE7 then it renders properly.  The problem with running DocumentMode = IE7 is that it breaks other control rendering.
Is there a work-around for this?
Thanks,
cj