<script type="text/javascript">
arrayClasses = document.getElementsByName('slides');
arrayClasses[0].className = 'visible';
i = 0;

function roda()
{
 esconde = (i == 0) ? 0 : i;
 
 if((arrayClasses.length - 1) == i)
 {
  mostra = 0;
  i = 0;
 } else {
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 }

 arrayClasses[esconde].className = 'hidden';
 arrayClasses[mostra].className = 'visible';
}

setInterval('roda()', 3000);
</script> 
