We've written up a little chunk of code that clears your chat history for you. Here's how to use it:

  1. First, copy and paste the following code into a Notepad file:
  2. <?php 
    $lov_CC = fopen('publicchat.txt', 'w') or die("can't open file"); 
    echo 'Chat Log Successfully Cleared!'; 
  3. Save it as clearpubchat.php.
  4. Using an FTP client like Direct FTP or Free FTP, upload it to the same location where your chat files are saved.
Now whenever the administrator wants to clear the public chat history, just go to that file in a browser. For example, if you saved the file in your server root, you would just have to go to http://www.yoursite.com/clearpubchat.php. 
Note: This will permanently remove the public chat history, meaning you cannot undo this action or recover any lost data. Consider yourself warned!