<com:TContent ID="Content"> <h2><strong>Without</strong> GroupName it is OK</h2> <com:TRadioButton ID="radio1" Text="Radio Button 1" /><br/> <com:TRadioButton ID="radio2" Text="Radio Button 1" /><br/> <com:TActiveButton id="button1" OnCallback="noGroup" Text="test without GroupName" /> <br/><br/> <h2>But with the same...</h2> <com:TRadioButton ID="bad_radio1" GroupName="bad" Text="Bad Radio Button 1" /><br/> <com:TRadioButton ID="bad_radio2" GroupName="bad" Text="Bad Radio Button 1" /><br/> <com:TActiveButton id="button2" OnCallback="group" Text="test with a GroupName" /> <com:TActiveLabel ID="label1" Text="Label 1"/> </com:TContent>