Doesn't count the right downloaded files

I work with Drupal 5 and Download Counter 5.x-1.0 module.

I have a content-type called Document which allows to attach a file. In my example (issue.PNG) I have the file BI.doc

I changed a part of download_count.module (code given here : http://drupal.org/node/110125#comment-199181)

<?php
function download_count_file_download($filename) {

  $file = file_create_path($filename);
  $result = db_query("SELECT f.* FROM {files} f WHERE filepath = '%s'", $file);
  if ($file = db_fetch_object($result)) {
    if (user_access('view uploaded files') && node_access('view', node_load($file->nid))) {
      $message = t('%file was downloaded', array('%file' => theme('placeholder', $filename)));
      watchdog('download', $message, WATCHDOG_NOTICE);       
      // If the file is already added, just increment the count,
      // otherwise add the file with count 1
      if(db_result(db_query("SELECT filename FROM {file_downloads} WHERE filename = '$filename'"))) {
        db_query("UPDATE {file_downloads} SET count = count+1 WHERE filename = '$filename'");
      }
      else {
        db_query("INSERT INTO {file_downloads} (filename, count) VALUES ('$filename', 1)");
      }           
    }
    else {
      $message = t('Failed to download %file', array('%file' => theme('placeholder', $filename)));    
      watchdog('download', $message, WATCHDOG_WARNING);
    }   
  }
}
?>

Now when I download one file counter's incrementation is one.
But the counter takes two wrong files images/PhotoBB 116.thumbnail.jpg and images/PC282766.thumbnail.JPG instead of BI.doc. Moreover the value for last update is 38 years 32 weeks ago.

Anybody to help me to solve this problem please ?

Regards,

Nicolas