function preloader() 
{
    // counter     
	var i = 0;
     // create object     
	imageObj = new Image();
     // set image list    
	 images = new Array();    
 	images[0]="sidenav_r2_c2_f2.gif"     
	images[1]="sidenav_r3_c2_f2.gif"     
	images[2]="sidenav_r4_c2_f2.gif"     
	images[3]="sidenav_r5_c2_f2.gif"
     // start preloading    
 	for(i=0; i<=3; i++)   
   {         
 	imageObj.src=images[i];  
   }

}