currentButtonState = "workoutsBtn";
	
  // PRELOADING IMAGES
  if (document.images) {
    workoutsBtn_active = new Image(); workoutsBtn_active.src = "/images/workouts_active.jpg"; 
    workoutsBtn_hover  = new Image(); workoutsBtn_hover.src  = "/images/workouts_over.jpg"; 
    workoutsBtn_normal = new Image(); workoutsBtn_normal.src = "/images/workouts_normal.jpg"; 

    historyBtn_active  = new Image(); historyBtn_active.src  = "/images/history_active.jpg"; 
    historyBtn_hover   = new Image(); historyBtn_hover.src   = "/images/history_over.jpg"; 
    historyBtn_normal  = new Image(); historyBtn_normal.src  = "/images/history_normal.jpg"; 

    prefsBtn_active = new Image();    prefsBtn_active.src = "/images/preferences_active.jpg"; 
    prefsBtn_hover  = new Image();    prefsBtn_hover.src  = "/images/preferences_over.jpg"; 
    prefsBtn_normal = new Image();    prefsBtn_normal.src = "/images/preferences_normal.jpg"; 
   }

   // EVENT HANDLERS
   function pressButton(btName) {
     if (document.images) {
		   if (currentButtonState != "")
			   eval('document.'+currentButtonState+'.src='+currentButtonState+'_normal.src');
				 
  	   currentButtonState = btName;
       eval('document.'+btName+'.src='+btName+'_active.src');
		 }
   }

   function hoverButton(btName) {
     if (document.images) {
       eval('document.'+btName+'.src='+btName+'_hover.src');
     }
	 }
	 
   function releaseButton(btName) {
		 if (document.images) {
		   if (currentButtonState == btName) 
         eval('document.'+btName+'.src='+btName+'_active.src');
			 else
         eval('document.'+btName+'.src='+btName+'_normal.src');
     }
	 }