function mouseOver1()
{
document.getElementById("a1").src="images/bg/btn_home_over.gif"
}
function mouseOut1()
{
document.getElementById("a1").src="images/bg/btn_home.gif"
}



function mouseOver2()
{
document.getElementById("a2").src="images/bg/btn_aboutus_over.gif"
}
function mouseOut2()
{
document.getElementById("a2").src="images/bg/btn_aboutus.gif"
}

function mouseOver3()
{
document.getElementById("a3").src="images/bg/btn_services_over.gif"
}
function mouseOut3()
{
document.getElementById("a3").src="images/bg/btn_services.gif"
}

function mouseOver4()
{
document.getElementById("a4").src="images/bg/btn_contactus_over.gif"
}
function mouseOut4()
{
document.getElementById("a4").src="images/bg/btn_contactus.gif"
}