Testing for tidy binary on linux fails, but tidy actually works as desired

This bug occurs on a virtual server running SuSE 7.5:

htmltidy.module tries to find the tidy binary.
If the file is found, a test is run (line 528) to get the tidy version (i think) with
$result = exec('tidy -v', $response)

normally, the response from tidy is a single line with version info, but on that SuSE system, the resposne is

[empty line]
HTML Tidy for Linux/x86 (release date: ...
See http://... for details

the first empty line seems to cause the problem, that tidy executable is found but not used (this is, what the drupal error message says).

I tried to fix the bug like this:

  // now test it
  $command = escapeshellcmd("$tidypath -v");
  # drupal_set_message("Running command <br/>\n$command", 1);
  // old
  //$result = exec($command, $response); // works on Gentoo linux, not on SuSE 7.5

  // new
  passthru($command, $result); // $result of 0 is: no error, actually does not return the version number of tidy; see http://de3.php.net/manual/en/function.passthru.php

  if(0 != $result){
    $message = "Found 'tidy' binary, but it didn't run right. \n$command\nfailed to respond correctly";
    return FALSE;
  }

  # drupal_set_message("Looks like tidy is ready for use! ".$result);
  $message = $result;
  return TRUE;
} // function htmltidy_test

maybe this helps somebody.