$txt = preg_replace( "#<!--code1-->(.+?)<!--ecode1-->#", '[code]', $txt );
$txt = preg_replace( "#<!--code2-->(.+?)<!--ecode2-->#", '', $txt );

$txt = preg_replace( "#<!--tak1-->(.+?)<!--etak1-->#", '[tak]', $txt );
$txt = preg_replace( "#<!--tak2-->(.+?)<!--etak2-->#", '[/tak]', $txt );

$source = preg_replace( "#\[code\](.+?)\[/code\]#is", "<!--code1--><div class=\"scriptcode\"><!--ecode1-->\\1<!--code2--></div><!--ecode2-->", $source );

$source = preg_replace( "#\[tak\](.+?)\[/tak\]#is", "<!--tak1--><div>Кликните по рекламе Tak.ru чтобы увидить Скрытый текст</div><div style=\"background-color:#99CCFF\" ><div id=\"hidden\" style=\"display:none;\" class=\"scriptcode\"><!--etak1-->\\1<!--tak2--></div></div><!--etak2-->", $source );

<div id="b_quote" class="editor_button" onclick="simpletag('quote')"><img title="$lang[bb_t_quote]" src="engine/skins/bbcodes/images/quote.gif" width="23" height="25" border="0"></div>

<div id="b_tak" class="editor_button" onclick="simpletag('tak')"><img title="Скрытый текст за рекламу" src="engine/skins/bbcodes/images/tak.gif" width="23" height="25" border="0"></div>

</body>

<script>
function payForFiles(){ 
             var hid,tak,elems,num,pat,j,i; 
         hid = document.getElementById("hidden"); 
         tak = new Array(); 
  elems = document.getElementsByTagName('A'); 
                                     num = elems.length; 
           pat = new RegExp("(^|\\b)(takru)(\\b|$)"); 
  j = 0; 
  for (i=0;i<num;i++){ 
                    if(pat.test(elems[i].className)){ 
          elems[i].setAttribute('target','_blank'); 
          if (elems[i].addEventListener) 
        elems[i].addEventListener("click", function(){hid.style.display = ""}, false); 
        else if (elems[i].attachEvent) 
         elems[i].attachEvent("onclick", function(){hid.style.display = ""}); 
  else elems[i].onclick = function(){hid.style.display = ""}; 
      j++;} 
      } 
      }; 
payForFiles(); 
</script>