a_off      = new Image (144,23);
a_off.src  = "pics/bt_HomeSearch.gif";
a_on       = new Image (144,23);
a_on.src   = "pics/bt_HomeSearchOn.gif";

b_off      = new Image (160,23);
b_off.src  = "pics/bt_BusSearch.gif";
b_on       = new Image (160,23);
b_on.src   = "pics/bt_BusSearchOn.gif";

c_off      = new Image (156,23);
c_off.src  = "pics/bt_FindAgent.gif";
c_on       = new Image (90,18);
c_on.src = "pics/bt_FindAgentOn.gif";


//--------------------------------------


gr1_off = new Image(143, 20);
gr1_off.src = "pics/grHome.gif";
gr1_on = new Image(143, 20);
gr1_on.src = "pics/grHome_on.gif";

gr2_off = new Image(143, 20);
gr2_off.src = "pics/grBus.gif";
gr2_on = new Image(143, 20);
gr2_on.src = "pics/grBus_on.gif";

gr3_off = new Image(143, 20);
gr3_off.src = "pics/grAgent.gif";
gr3_on = new Image(143, 20);
gr3_on.src = "pics/grAgent_on.gif";

gr4_off = new Image(143, 20);
gr4_off.src = "pics/grArticles.gif";
gr4_on = new Image(143, 20);
gr4_on.src = "pics/grArticles_on.gif";


function imageReplace(imgid,imgnew)
   {
   document.images[imgid].src=eval(imgnew + ".src");
   }