Dissolvenza On Mouse Over

<script type="text/javascript">
function high(which2){
theobject=which2
highlighting=setInterval("highlightit(theobject)",50)
}
function low(which2){
clearInterval(highlighting)
if (which2.style.MozOpacity)
which2.style.MozOpacity=0.3
else if (which2.filters)
which2.filters.alpha.opacity=30
}
function highlightit(cur2){
if (cur2.style.MozOpacity<1)
cur2.style.MozOpacity=parseFloat(cur2.style.MozOpacity)+0.1
else if (cur2.filters&&cur2.filters.alpha.opacity<100)
cur2.filters.alpha.opacity+=10
else if (window.highlighting)
clearInterval(highlighting)
}</script>

<a href="LINK"><img src="LINK IMMAGINE" alt="BLABLA" targhet="_blank" onmouseover="high(this)" style="opacity: 0.3;" onmouseout="low(this)" border="0" width="58" height="20"></a>