The excel lib problem

[eluser]whidbey[/eluser]
the following is the plugin for excel file gereration.
but the output excel file don't support chinese words ,even I have set
UTF-8 query from database. how can I resolve it? thx very much

Code:

<?php if (!defined('BASEPATH')) exit('No direct script access allowed');
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/*
* Excel library for Code Igniter applications
* Author: Derek Allard, Dark Horse Consulting, www.darkhorse.to, April 2006
*/

function to_excel($query, $filename='exceloutput')
{
     $headers = ''; // just creating the var for field headers to append to below
     $data = ''; // just creating the var for field data to append to below
    
     $obj =& get_instance();
    
     $fields = $query->field_data();
     if ($query->num_rows() == 0) {
          echo '<p>The table appears to have no data.</p>';
     } else {
          foreach ($fields as $field) {
             $headers .= $field->name . "\t";
          }
    
          foreach ($query->result() as $row) {
               $line = '';
               foreach($row as $value) {                                            
                    if ((!isset($value)) OR ($value == "")) {
                         $value = "\t";
                    } else {
                         $value = str_replace('"', '""', $value);
                         $value = '"' . $value . '"' . "\t";
              
                    }
                    $line .= $value;
               }
               $data .= trim($line)."\n";
          }
          
          $data = str_replace("\r","",$data);
          header("Content-type:application/vnd.ms-excel");
          header("Content-Disposition:filename=$filename.xls");                
          //header("Content-type: application/x-msdownload");
          //header("Content-Disposition: attachment; filename=$filename.xls");
          echo "$headers\n$data";  
     }
}
?&gt;

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