Two User Controls - each with OnDblClick event - when one doubleclicked both events get fired

I have a page with two listboxes on it...both of these listboxes are individual user controls. They have an event handler for OnDblClick for double click support.

 

But when one listbox has an item double clicked, both double click events get fired...am I doing something wrong in my code???

 

Thanks.

 Here isthe code for user control and page where the listboxes are put....

 ===========================================================

 public partial class ucListControl : BaseUserControl
 {

  protected void Page_Load( object sender, EventArgs e )
  {
   //08/13/2008 SAM  Issue:83
   if ( Request[ "__EVENTARGUMENT" ] != null && Request[ "__EVENTARGUMENT" ] == "doubleclick" )
   {
    this.OnDoubleClick( EventArgs.Empty );
...