image1 = new Image();
image1.src = "img/home.gif";

image2 = new Image();
image2.src = "img/search.gif";

image3 = new Image();
image3.src = "img/material.gif";

image4 = new Image();
image4.src = "img/clink.gif";

image5 = new Image();
image5.src = "img/mlink.gif";

image6 = new Image();
image6.src = "img/ref.gif";

 function msout(num) {
	if (num== 1) document.img_btn1.src = image1.src;
	if (num== 2) document.img_btn2.src = image2.src;
	if (num== 3) document.img_btn3.src = image3.src;
	if (num== 4) document.img_btn4.src = image4.src;
	if (num== 5) document.img_btn5.src = image5.src;
	if (num== 6) document.img_btn6.src = image6.src;

}

function msover(num) {
	if (num == 1) document.img_btn1.src = "img/home_ov.gif";
	if (num == 2) document.img_btn2.src = "img/search_ov.gif";
	if (num == 3) document.img_btn3.src = "img/material_ov.gif";
	if (num == 4) document.img_btn4.src = "img/clink_ov.gif";
	if (num == 5) document.img_btn5.src = "img/mlink_ov.gif";
	if (num == 6) document.img_btn6.src = "img/ref_ov.gif";

}