DetailsView - EditItemTemplate - field validator???

[K B]

I need to validate fields in a DetailsView when the user clicks Update.
In Insert, I use:

<asp:RequiredFieldValidator ID="RequiredFieldValidator2"
ValidationGroup="InitiateJobEdit"
ControlToValidate="DropDownList1"
InitialValue="0" Text="(select one)" Runat="Server" />

in the EditItemTemplate source. Nothing fires.

PLEASE tell me what I'm missing.

Thanks,
Kit