l2_on = new Image;
l2_on.src = "kn/m2+.gif";  
l2_off = new Image;
l2_off.src = "kn/m2.gif"; 
l3_on = new Image;
l3_on.src = "kn/m3+.gif";  
l3_off = new Image;
l3_off.src = "kn/m3.gif"; 
l4_on = new Image;
l4_on.src = "kn/m4+.gif";  
l4_off = new Image;
l4_off.src = "kn/m4.gif"; 
l5_on = new Image;
l5_on.src = "kn/m5+.gif";  
l5_off = new Image;
l5_off.src = "kn/m5.gif"; 
l6_on = new Image;
l6_on.src = "kn/m6+.gif";  
l6_off = new Image;
l6_off.src = "kn/m6.gif";
l7_on = new Image;
l7_on.src = "kn/m7+.gif";  
l7_off = new Image;
l7_off.src = "kn/m7.gif"; 
l8_on = new Image;
l8_on.src = "kn/m8+.gif";  
l8_off = new Image;
l8_off.src = "kn/m8.gif"; 
l9_on = new Image;
l9_on.src = "kn/m9+.gif";  
l9_off = new Image;
l9_off.src = "kn/m9.gif"; 
function ButtonOn(buttonId)
{if ((document.images))
{imgOn = eval("l" + buttonId + "_on.src");
document.images["l" +buttonId].src = imgOn;}}
function ButtonOff(buttonId)
{if ((document.images))
{imgOff = eval("l" + buttonId + "_off.src");
document.images["l" +buttonId].src = imgOff;}}