var base_url=location.href;
base_url=base_url.substring(0,base_url.lastIndexOf("/")+1);
base_url=base_url.substring(0,base_url.lastIndexOf("cgi-bin/"));
var imgs=new Array(7);
imgs[0]=base_url+"images/menu_r1_c9.jpg";
imgs[1]=base_url+"images/menupic2.jpg";
imgs[2]=base_url+"images/menupic3.jpg";
imgs[3]=base_url+"images/menupic4.jpg";
imgs[4]=base_url+"images/menupic5.jpg";
imgs[5]=base_url+"images/menupic6.jpg";
imgs[6]=base_url+"images/menupic7.jpg";

var rimg=document.images['menu_r1_c9'];

rimg.src=imgs[Math.floor(Math.random() * imgs.length)];