function leftNav(currNum) {

    if (currNum == undefined)
        currNum = "1";
    if (currNum != "undefined")
    //if (document.all&&document.getElementById) 

        if (document.getElementById) {
        navRoot = document.getElementById("leftNav");

        for (i = 0; i < navRoot.childNodes.length; i++) {
            node = navRoot.childNodes[i];
            if (node.nodeName == "LI") {
                xID = getElementId(node.getAttribute("ID"));
                if (xID == currNum) {
                    document.getElementById('sm' + Number(xID)).style.display = 'block';
                    document.getElementById('ln' + Number(xID)).className = 'active';
                }
                else {
                    if (document.getElementById('sm' + Number(xID)) != null)
                        document.getElementById('sm' + Number(xID)).style.display = 'none';
                    if (document.getElementById('sm' + Number(xID)) != null)
                        document.getElementById('ln' + Number(xID)).className = '';


                }
            }
        }
    }
}

function getElementId(tagId) {
    var iLen = tagId.length;
    var iRet = 0;
    var pFix = Number(iLen) -2;
    
    iRet = tagId.substring(2, (2 + pFix));
    //alert(" iRet : " + iRet);
    /*
    if (Number(iLen) == 3)
        iRet = tagId.substring(2, 3);
    else if (Number(iLen) == 4)
        iRet = tagId.substring(2, 5);
    else
        iRet = tagId.substring(2, 4);
    */
    return iRet;
}