var checkboxes;
var checkOff = '../images/check_off.gif';
var checkOn = '../images/check_on.gif';
function loadchecks() {
    loadMyChecks();
}

function loadMyChecks() {
    
    checkboxes = document.getElementsByTagName('input');
    for(var i=0; i < checkboxes.length; i++) {
        if(checkboxes[i].getAttribute('type') == 'checkbox') {
            var img = document.createElement('img');
            
            if(checkboxes[i].checked) {
                img.src = checkOn;
            } else {
                img.src = checkOff;
            }

            img.id = 'checkImage'+i;
            img.onclick = new Function('checkChange('+i+')');
            checkboxes[i].parentNode.insertBefore(img, checkboxes[i]);
            
            checkboxes[i].style.display='none';
        }
    }
}

function checkChange(i) {

    if(checkboxes[i].checked) {
        checkboxes[i].checked = '';
        document.getElementById('checkImage'+i).src=checkOff;
    } else {
        checkboxes[i].checked = 'checked';
        document.getElementById('checkImage'+i).src=checkOn;
    }
}

window.onload = loadchecks;