Supongo que debe ser esto...
Es la primera vez que veo algo igual.
Curioso.
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<script language="JavaScript">
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function MM_swapImgRestore() { //v3.0
var i,x,a=document.MM_sr; for(i=0;a&&i<a.length&&(x=a[i])&&x.oSrc;i++) x.src=x.oSrc;
}
function MM_preloadImages() { //v3.0
var d=document; if(d.images){ if(!d.MM_p) d.MM_p=new Array();
var i,j=d.MM_p.length,a=MM_preloadImages.arguments; for(i=0; i<a.length; i++)
if (a[i].indexOf("#")!=0){ d.MM_p[j]=new Image; d.MM_p[j++].src=a[i];}}
}
function MM_findObj(n, d) { //v4.0
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d=parent.frames[n.substring(p+1)].document; n=n.substring(0,p);}
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if(!x && document.getElementById) x=document.getElementById(n); return x;
}
function MM_swapImage() { //v3.0
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<td width="176"><a href="photoshop/photosho.htm" onMouseOut="MM_swapImgRestore()" onMouseOver="MM_swapImage('Image2','','truc2.jpg', 1)"><img name="Image2" border="0" src="truc1.jpg" width="176" height="251"></a></td>
<td width="176"><a href="fondos.htm" onMouseOut="MM_swapImgRestore()" onMouseOver="MM_swapImage('Image3','','back2.jpg', 1)"><img name="Image3" border="0" src="back1.jpg" width="176" height="251"></a></td>
<td width="176"><a href="http://club2.telepolis.com/letera" onMouseOut="MM_swapImgRestore()" onMouseOver="MM_swapImage('Image4','','font2.jpg', 1)"><img name="Image4" border="0" src="font1.jpg" width="176" height="251"></a></td>
<td width="176"><a href="efectos/main.html" onMouseOut="MM_swapImgRestore()" onMouseOver="MM_swapImage('Image5','','jav2.jpg',1 )"><img name="Image5" border="0" src="jav1.jpg" width="176" height="251"></a></td>