if (document.images) {            // Active Images
        imgnav1on = new Image();      
        imgnav1on.src = "images/about-on.jpg"; 
        imgnav2on = new Image();      
        imgnav2on.src = "images/coverage-on.jpg"; 
        imgnav3on = new Image();      
        imgnav3on.src = "images/contact.jpg"; 
        imgnav4on = new Image();      
        imgnav4on.src = "images/customer.jpg"; 

        imgnav1off = new Image();      
        imgnav1off.src = "images/about.jpg"; 
        imgnav2off = new Image();      
        imgnav2off.src = "images/coverage.jpg"; 
        imgnav3off = new Image();      
        imgnav3off.src = "images/contact.jpg"; 
        imgnav4off = new Image();      
        imgnav4off.src = "images/customer.jpg"; 
}

function show_coverage(s) {
        if (s == 1) {
                document.getElementById('coverage_nav').style.visibility = 'visible';
                document.getElementById('coverage_nav').style.display = 'block';
        } else {
                document.getElementById('coverage_nav').style.visibility = 'hidden';
                document.getElementById('coverage_nav').style.display = 'none';
        }
}

sfHover = function() {
        var sfEls = document.getElementById("nav").getElementsByTagName("LI")
        for (var i=0; i<sfEls.length; i++) {
                sfEls[i].onmouseover=function() {
                        this.className+=" ExplorerHover"
                }
                sfEls[i].onmouseout=function() {
                        this.className=this.className.replace(new RegExp(" ExplorerHover\\b"), "")
                }
        }
}
if (window.attachEvent)
        window.attachEvent("onload", sfHover)