Custom cell renderer granularity

[dhiren9]

My custom cell renderer works when I set it at the <DataGridColumn> 
level, however it does not take effect when I set it for the entire 
<DataGrid> tag.

I don't use the <DataGridColumn> tags since my grid is populated 
using a DataProvider. Am I missing something here? Also, how do I 
modify the column headers to use my custom cell renderer.

Thanks.

-D