How do I use validation controls on a dropdown list

Hello all
Please I need help with this... I have a dropdown list control which I populate at run time with the first item being like "-- Select an Item --", for example. I need the user to select an item from the list apart from the first item displayed. I tried using required field validators and setting the InitialValue property to "-- Select an Item --". But this does not seem to work.
Any ideas? please note that the dropdown list is programmtically populated based on certain decisions presented to the user.


Thanks.

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