non mi funziona...

[CODE]

<style>
.disable {background-color: silver;color: white;}
</style>


<script>var old=-1;</script>


<select id="descrizione_breve" name="descrizione_breve">

<option value=""></option>

<option value="01" class="disable" onclick="old=this.selectedIndex;alert(old);" onchange="if(this.options[this.selectedIndex].className=='disable') this.selectedIndex=old">Pagina principale</option>


<option value="02" class="disable" onclick="old=this.selectedIndex" onchange="if(this.options[this.selectedIndex].className=='disable') this.selectedIndex=old">Pagina 2</option>


<option value="03" onclick="old=this.selectedIndex" onchange="if(this.options[this.selectedIndex].className=='disable') this.selectedIndex=old">Pagina 3</option>


<option value="04" onclick="old=this.selectedIndex" onchange="if(this.options[this.selectedIndex].className=='disable') this.selectedIndex=old">Pagina 4</option>

</select>
[</CODE]