Open bbcode_code template at top add this:

Code: 
<script type="text/javascript"> 
function selectCode(a) 
{ 
   var e = a.parentNode.parentNode.getElementsByTagName('PRE')[0]; 
   if (window.getSelection) 
   { 
      var s = window.getSelection(); 
       if (s.setBaseAndExtent) 
      { 
         s.setBaseAndExtent(e, 0, e, e.innerText.length - 1); 
      } 
      else 
      { 
         var r = document.createRange(); 
         r.selectNodeContents(e); 
         s.removeAllRanges(); 
         s.addRange(r); 
      } 
   } 
   else if (document.getSelection) 
   { 
      var s = document.getSelection(); 
      var r = document.createRange(); 
      r.selectNodeContents(e); 
      s.removeAllRanges(); 
      s.addRange(r); 
   } 
   else if (document.selection) 
   { 
      var r = document.body.createTextRange(); 
      r.moveToElementText(e); 
      r.select(); 
   } 
} 
</script>
Find:
PHP Code: 
$vbphrase[code]: 
Replace with:
PHP Code: 
$vbphrase[code]: <a href="#" onclick="selectCode(this); return false;">Select All</a