browserName = navigator.appName;

browserVer = parseInt ( navigator.appVersion );

version = "n2";

if ( browserName == "Netscape" && browserVer >= 3 ) version = "n3";

if ( browserName == "Microsoft Internet Explorer" && browserVer >=4 ) version = "e4";



if ( version == "n3" || version == "e4" )

{

	left_on = new Image ( 40, 40 );
	left_on.src = "images/left_on.gif";

	left_off = new Image ( 40, 40 );
	left_off.src = "images/left_off.gif";

	right_on = new Image ( 40, 40 );
	right_on.src = "images/right_on.gif";

	right_off = new Image ( 40, 40 );
	right_off.src = "images/right_off.gif";

	up_on = new Image ( 40, 40 );
	up_on.src = "images/up_on.gif";

	up_off = new Image ( 40, 40 );
	up_off.src = "images/up_off.gif";

}


function button_on ( imgName )

{

        if ( version == "n3" || version == "e4" )

        {

                butOn = eval ( imgName + "_on.src" );

                document [imgName].src = butOn;

        }

}



function button_off ( imgName )

{

        if ( version == "n3" || version == "e4" )

        {

                butOff = eval ( imgName + "_off.src" );

                document [imgName].src = butOff;

        }

}