browserName = navigator.appName; 
browserVer = parseInt(navigator.appVersion);  
if (browserName == "Netscape" && browserVer >= 3) { browserCheck = "ok"; }  
else {       
if (browserName == "Microsoft Internet Explorer" && browserVer >= 3) { browserCheck = "ok"; }      
else { browserCheck = "bad"; }  }  
if (browserCheck == "ok") 
{   
b0a = new Image(); 
b0a.src = "but0.gif"; 
b0b = new Image(); 
b0b.src = "but0a.gif"; 
b1a = new Image(); 
b1a.src = "but1.gif"; 
b1b = new Image(); 
b1b.src = "but1a.gif"; 
b2a = new Image(); 
b2a.src = "but2.gif"; 
b2b = new Image(); 
b2b.src = "but2a.gif"; 
b3a = new Image(); 
b3a.src = "but3.gif"; 
b3b = new Image(); 
b3b.src = "but3a.gif"; 
b4a = new Image(); 
b4a.src = "but4.gif"; 
b4b = new Image(); 
b4b.src = "but4a.gif"; 
b5a = new Image(); 
b5a.src = "but5.gif"; 
b5b = new Image(); 
b5b.src = "but5a.gif"; 
b6a = new Image(); 
b6a.src = "but6.gif"; 
b6b = new Image(); 
b6b.src = "but6a.gif"; 
b7a = new Image(); 
b7a.src = "but7.gif"; 
b7b = new Image(); 
b7b.src = "but7a.gif"; 
b8a = new Image(); 
b8a.src = "but8.gif"; 
b8b = new Image(); 
b8b.src = "but8a.gif"; 
b9a = new Image(); 
b9a.src = "but9.gif"; 
b9b = new Image(); 
b9b.src = "but9a.gif"; 
b10a = new Image(); 
b10a.src = "but10.gif"; 
b10b = new Image(); 
b10b.src = "but10a.gif"; 

}  
function imgswap( Iname1, Iname2) { if (browserCheck == "ok") { document [Iname1].src = eval(Iname2 + ".src"); } }