function highlight1(img) 	{ document[img].src = "navi/" + img + "_on.jpg"; }
function unhighlight1(img) 	{ document[img].src = "navi/" + img + "_off.jpg"; }

function highlight2(img) 	{ document[img].src = "navi/portfolio/" + img + "_on.jpg"; }
function unhighlight2(img) 	{ document[img].src = "navi/portfolio/" + img + "_off.jpg"; }