RequiredFieldvalidator with RadioButtonList

Hi,
 
I've A Wizard and inside it a RadioButtonList with only one item (one radiobutton) and I have assigned to it a RequiredFieldValidator and the problem it that with that only radiobuttonlist selected the RequiredFieldValidator is still not letting going any further and still asking my to select an option from the radiobuttonlist, knowing and as I menssioned earlier that my radiobuttonlist control has only one item and it's selected
 
Thanks
 
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