DataGrid Error Icon not appearing

[Evil Joe]

I have an Asp.net application that allows someone to load a datagrid
from an Excel Spreadsheet and then validate the contents of the
datagrid.

I was validating the grid by checking the rows and setting the
SetColumnError and RowError properties of the data table row where
appropriate. But, when I bind the datatable to the grid the Error
Icons don't show up on the page. Is this a Windows Form feature only?
I have been searching everywhere for a tip but have not located
anything...

Code
====
For Each drRow In dsSSheet.Tables("Sheet1").Rows


If Not IsValid(drRow) Then

drRow.SetColumnError(0, "Bunny Fluff not found")
drRow.RowError = "Policy Type is invalid"

End If
Next

dgResults.DataSource = dsSSheet.Tables("Sheet1")
dgResults.DataBind()