function getE(e){
  if(document.getElementById(e)!=undefined){
    return document.getElementById(e);
  }else{
    return false;
  }
}
function fadeFeature(){
  var divs = new Array();
  divs[0]="feature_1" ;
  divs[1]="feature_2" ;
  divs[2]="feature_3" ; 
  divs[3]="feature_4" ; 

  divs[4]="feature_1" ;

  for(i=0;i<divs.length;i++){
    if((getE(divs[i]))&&(getE(divs[i+1]))&&(getE(divs[i]).style.display!='none')){
      new Effect.Fade(divs[i],{queue:'front',duration:1.0});
      new Effect.Appear(divs[i+1],{queue:'end',duration:1.0});
    }
  }
}