<?php
error_reporting(E_ALL ^ E_NOTICE);
if (!defined('IN_EXBB')) die('Hack attempt!');
function meta_description() {
global $allforums,$topic;
if(isset($_GET['topic'])) {
if(isset($_GET['p'])) {$pn=' - Страница '.$_GET['p'];$pd='Страница '.$_GET['p'].' - ';}
else {$pn='';$pd='';}
$mt=$topic['name'].$pn;
$md=$pd.str_replace('Описание: ','',$topic['desc']).' - '.$topic['name'];
}
elseif(isset($_GET['forum'])) {
$mt=$allforums[$_GET['forum']]['name'].' - '.$allforums[$_GET['forum']]['catname'];
$d=trim($allforums[$_GET['forum']]['desc']);
if(!empty($d)) {$de=$d.' - ';}
else {$de='';}
$md=$de.$mt;
}
elseif(isset($_GET['c'])) {
for($i=1;$i<=count($allforums);$i++) {
if(($allforums[$i]['catid'])==$_GET['c']) {
$mt=$allforums[$i]['catname'];
$md=$allforums[$i]['catname'].' - '.$GLOBALS['fm']->exbb['boardname'];
break;}
}
}
else {
$mt=$GLOBALS['fm']->exbb['boardname'];;
$md=$GLOBALS['fm']->exbb['boarddesc'];
}
$mt=array($mt,$md);
return $mt;
}
$mtag=meta_description();
$ptitle=$mtag[0];
$metadesc=$mtag[1];
unset($mtag);
?>

...
<title>{$ptitle}</title>
...
<meta name="description" content="{$metadesc}">
<meta http-equiv="description" content="{$metadesc}">
<meta name="Keywords" content="{$ptitle}">
<meta http-equiv="Keywords" content="{$ptitle}">
...

AddDefaultCharset windows-1251