browserName = navigator.appName;
browserVer = parseInt(navigator.appVersion);
if (browserName == "Netscape" && browserVer >= 3 || browserName == "Microsoft Internet Explorer" && browserVer>=4) {
        version = "n3";
}
else {
        version = "x";
} 
 if (version == "n3")
 {
 block1on = new Image();   
	block1on.src = "imgs/pz10_on.gif"; 
  block1off = new Image();   
	block1off.src = "imgs/pz10_off.gif";


block2on = new Image();   
	block2on.src = "imgs/messenger_on.gif"; 
  block2off = new Image();   
	block2off.src = "imgs/messenger_off.gif";

block3on = new Image();   
	block3on.src = "imgs/forum_on.gif"; 
  block3off = new Image();   
	block3off.src = "imgs/forum_off.gif";

block4on = new Image();   
	block4on.src = "imgs/gallery_on.gif"; 
  block4off = new Image();   
	block4off.src = "imgs/gallery_off.gif";

block5on = new Image();   
	block5on.src = "imgs/videos_on.gif"; 
  block5off = new Image();   
	block5off.src = "imgs/videos_off.gif";

block6on = new Image();   
	block6on.src = "imgs/mobiles_on.gif"; 
  block6off = new Image();   
	block6off.src = "imgs/mobiles_off.gif";

block7on = new Image();   
	block7on.src = "imgs/wallpapers_on.gif"; 
  block7off = new Image();   
	block7off.src = "imgs/wallpapers_off.gif";
}

function img_act(imgName)  
{   
if (version == "n3")   
{  
 imgOn = eval(imgName + "on.src");   
document [imgName].src = imgOn;   }
}

function img_inact(imgName)   
{   
if (version == "n3") 
{   
imgOff = eval(imgName + "off.src");   
document [imgName].src = imgOff;   
}
}