function ShowDialog()
{
    Effect.Appear("overlay",{from: 0, to: 0.7, duration: 0.5, afterFinish: 
    function()
    {
       Effect.Appear("dialog",{from:0, to:1, duration: 0.5});
    }});
}

function HideDialog()
{
   Effect.Fade("dialog",{from: 1, to: 0, duration: 0.5, afterFinish:
   function()
   {
      Effect.Appear("overlay", {from: 0.7, to: 0, duration: 0.5, afterFinish: 
      function()
      {
           $('overlay').style.display="none";
      }});
   }});

}