Columns and Inherited Datagrid...Active Schema does not support columns

[rob thomson]

I have a class which has inherited from datagrid, to provide some custom functionality, row select, mouse overs etc

All is working fine apart from after I add a column from the ide, within the HTML there is a red line saying
Active Schema does not support columns

Even this being the case I can still create and use the grid, and bind datasources to it

Does anyone know how I can get around this

Thanks