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Codice PHP:
<table id="tabellaesterna" width="100" height="100">
  <
tr>
    <
td align="center">
        <
table width="100"  height="100">
          <
tr>
            <
td width="100" 
                     
onMouseOver="getElementById('tabellaesterna').className='classe_70';" 
                     
onMouseOut ="getElementById('tabellaesterna').className='classe_60';">prova</td>
          </
tr>
        </
table>
    </
td>
  </
tr>
</
table