function header_language_compare($default = 'sr', $comparewith = 'hr') {
  $languages=split(',',$_SERVER["HTTP_ACCEPT_LANGUAGE"]);
  $qdefault=0;
  $qcompare=0;
  foreach ($languages as $lang) {
    if (ereg("^$default$",$lang,$regs)) {
      $qdefault=1;
    } elseif (ereg("^$comparewith$",$lang,$regs)) {
      $qcompare=1;
    } elseif (ereg("^$default;[ ]*q=([0-9.]+)$",$lang,$regs)) {
      $qdefault=$regs[1];
    } elseif (ereg("^$comparewith;[ ]*q=([0-9.]+)$",$lang,$regs)) {
      $qcompare=$regs[1];
    }
  }

  if ($qcompare>$qdefault) return 1;
  else return 0;
}

If "hr" is more desireable than "sr" (i.e. there's no "sr" at all, or it has lower "quality" than "hr") according to "Accept-Language" header, this function will return 1, otherwise 0. You might want to use something similar to compare 'en' and 'sq', letting most people default to 'en' for your blog.

It supports two languages (Serbian/Serbian transcription in Latin script and English), and I use the "current-group-language" as a group parameter to set the language per-group (so, for instance, gnom@prevod,org has it set to "sr", lugy@linux,org,yu set to "sr@Latn", and Gnome lists to "en").

As you might notice, I'm using local time for quoting, which makes sense since I don't want to put a timezone in the time. Also, it makes it easier to see how much time difference there was between a post and an answer (I find relative time measurements much easier, others may disagree ;).

So, no need to worry about quoting any more.

And it comes down to: use GNU Arch.

Update on 2016-10-05: fix links (reported by Marilyn Shaw—thanks!)