Ah scusate questo è il codice

<div id="BtnIniziative" style="position:absolute; left:58px; top:140px; width:120px; height:20px; z-index:1; background: #6699FF; layer-background-color: #6699FF; border: 1px none #000000;" onMouseOver="MM_showHideLayers('BtnEditoria','','s how')">Iniziative</div>

<div id="BtnEditoria" style="position:absolute; left:71px; top:162px; width:126px; height:20px; z-index:3; visibility: hidden; background: #0099CC; layer-background-color: #0099CC; border: 1px none #000000;" onMouseOver="MM_showHideLayers('BtnLibri','','show ')" >Editoria</div>

<div id="BtnLibri" style="position:absolute; left:112px; top:183px; width:96px; height:27px; z-index:4; visibility: hidden; background: #6666FF; layer-background-color: #6666FF; border: 1px none #000000;" onMouseOver="MM_showHideLayers('Layer1','','show') ">Libri</div>

Giorgio