private bool retriveByViewState;

protected override void LoadViewState(object savedState)
{
      if (((Triplet) savedState).Second != null)
      {
            this.retriveByViewState = true;
      }
      base.LoadViewState(savedState);
}

protected void Drop_PreRender(object sender, EventArgs e)
{
      if (((this.NeutralText.Length > 0) & (this.NeutralValue.Length > 0)) & !this.retriveByViewState)
      {
            this.Items.Insert(0, new ListItem(this.NeutralText, this.NeutralValue));
      }
}