if ( document.images )
{

home_on = new Image ( 79, 37 );
home_off = new Image ( 79, 37 );
home_on.src = "/images/nav/1_home_on.gif";
home_off.src = "/images/nav/1_home_off.gif";

aboutus_on = new Image ( 94, 37 );
aboutus_off = new Image ( 94, 37 );
aboutus_on.src = "/images/nav/2_aboutus_on.gif";
aboutus_off.src = "/images/nav/2_aboutus_off.gif";

calendar_on = new Image ( 92, 37 );
calendar_off = new Image ( 92, 37 );
calendar_on.src = "/images/nav/3_calendar_on.gif";
calendar_off.src = "/images/nav/3_calendar_off.gif";

media_on = new Image ( 88, 37 );
media_off = new Image ( 88, 37 );
media_on.src = "/images/nav/4_media_on.gif";
media_off.src = "/images/nav/4_media_off.gif";

resources_on = new Image ( 93, 37 );
resources_off = new Image ( 93, 37 );
resources_on.src = "/images/nav/5_resources_on.gif";
resources_off.src = "/images/nav/5_resources_off.gif";

contact_on = new Image ( 90, 37 );
contact_off = new Image ( 90, 37 );
contact_on.src = "/images/nav/6_contact_on.gif";
contact_off.src = "/images/nav/6_contact_off.gif";
}

function button_on ( imgName )
{
	if ( document.images )
	{

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

	}
}

function button_off ( imgName )
{
	if ( document.images )
	{

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

	}
}