Thanks Adam. I tried that. Now replace hello world with this CE tag:
<ce:Editor ID="ctlCuteEditor" Height="100%" Width="100%" runat="server" >
<FrameStyle BackColor="White" BorderColor="#DDDDDD" BorderStyle="Solid" BorderWidth="1px"
Height="100%" Width="100%"></FrameStyle>
</ce:Editor>
Check it out in firefox. You should see what I'm talking about - it doesn't fill the window - unless you remove doctype - which is not an option.