problem with custom GridView

[maz77]

I've created a custom GridView inside my GridVieBase.cs class:

namespace CustomControls{
public class GridViewBase : GridView
{...}
}

and then set the WebConfig as follows:

<controls>
<add tagPrefix="cc" namespace="CustomControls" />
</controls>

So I recall my custom GridView inside the page as:
<cc:GridViewBase ...etc

The problem is that I can add tag <Columnsbut I can't add
<TemplateFieldor <BoundField>.
I'm not sure that's the right way to inherit from Gridview...

Thanks

MAX