div.comment {
    position:absolute;
    left: -9999px;
    top: -9999px;
}
div.comment a.email_link {
    display: block;
    width: 16px;
    height: 16px;
    cursor: pointer;
    color: white;
    text-decoration:none;
    background: transparent url(comment_white_yellow.gif) no-repeat -16px 0;
}

div.comment a.email_link:hover{
    background-position:0 0;
}