[jQuery] Validate textbox on option selected value

[jQuery] Validate textbox on option selected value


Hi all,
I have this validate code to validate a textbox if the user select a
combo value:
<script type="text/javascript">
$(document).ready(function() {
    $("form#2form").validate({
    rules: {
viaAltro: {
required: "#AltraVia:checked"
}
},
messages: {
    viaAltro: {
required: "Insert 'Altra via'"
}
}
})
});
</script>
and this is the HTML:
<select name="viaFornitura" id="viaFornitura">
<option>Seleziona la via</option>
<option id="AltraVia">Altro</option>
</select>
<label for="viaAltro">Altra via</label>
<input name="viaAltro" id="viaFornituraAltro" type="text" />
but it doesn't work.
Where the problem?
Thanks a lot.
Luigi