Change BackColor in RadDataEntry Validation Panel

Dear all,

does anyone know how to change the BackColor ofthe RadDataEntry ValidationPanel.

I have tried various ways like setting it up at design time in Visual Studio,

or just before showing it at run time

                dataEntry.ValidationPanel.BackColor = Color.PapayaWhip;
                dataEntry.ShowValidationPanel = true;

and also via some event such as

  private void rdeDynamicInput_Initialized(object sender, EventArgs e)
    {
        ValidationPanel vpanel = (sender as RadDataEntry).ValidationPanel;
        if(vpanel != null) vpanel.BackColor = Color.PapayaWhip;
    }

Thanks for your answer