function formHandler(form)
{
var URL = form.menu.options[form.menu.selectedIndex].value;
location = URL;  
}

/*<form name="jump">
<select name="menu" onChange="location=document.jump.menu.options[document.jump.menu.selectedIndex].value;" value="GO">
<option value="http://wer">werwer</option>
<option value="http://werwer">werwer</option>
<option value="http://werwer">werwer</option>
</select>
</form>
*/