<com:TContent ID="Content"> <h1>Issue 504 Test</h1> <com:TPanel ID="dlg" DefaultButton="subPanel.buttonOk" > <com:TTextBox ID="textbox1" /> <com:TButton ID="buttonDummy" OnCommand="buttonDummyClick" Text="Dummy button" /> Panel Content <com:TLabel ID="label1" /> <com:TPanel ID="subPanel" > <com:TButton ID="buttonOk" OnCommand="buttonOkClick" Text="Ok button" /> </com:TPanel> </com:TPanel> </com:TContent>