<script type="text/javascript">  
  e=document.getElementsByTagName("TD");  
  for(k=0;k<e.length;k++) {  
  if(e[k].className=='posttdMessage') {  
  s=e[k].innerHTML;  
  while (s.indexOf('[T able]') != -1) {  
  s=s.replace('[T able]','<table width="100%" border="0" cellspacing="0" cellpadding="5" style="background-color:161618; border-top:1px dotted #898989; border-right:1px dotted #898989; border-bottom:1px dotted #898989; border-left:1px dotted #898989;"><tr><td style="width:25px; height:25px;background-repeat:no-repeat; background-position:5px 3px;"> </td><td><font style="font-size: 12px; font-family: Verdana; color: 898989;">'); s=s.replace('[/T able]','</font></td></tr></table>');  
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<input type="button" value="Таблица" onclick="simpletag('Table','','','message',''); return false;" class="codeButtons" title="Вставить Таблицу" name="Table"/>