var imageFiles_5_7 = new Array();
imageFiles_5_7['0'] = new Array ('_images/5_Home.gif', '_images/5_HomeMouseover.gif');
imageFiles_5_7['1'] = new Array ('_images/5_Contact_Us.gif', '_images/5_Contact_UsMouseover.gif');
imageFiles_5_7['2'] = new Array ('_images/5_Materials.gif', '_images/5_MaterialsMouseover.gif');
imageFiles_5_7['3'] = new Array ('_images/5_Services.gif', '_images/5_ServicesMouseover.gif');
imageFiles_5_7['4'] = new Array ('_images/5_Portfolio.gif', '_images/5_PortfolioMouseover.gif');

function image_on_5_7 (position) {
   var doc = eval("document.image5_7" + position);
   doc.src = imageFiles_5_7[position][1];
}

function image_off_5_7 (position) {
   var doc = eval("document.image5_7" + position);
   doc.src = imageFiles_5_7[position][0];
}