# this script are correct with the right signs remove expression
# please, ignore the later.
function decode_utf8($str){
       # paterns
           $err="(=\?.{10,13}q\?_?|\?\=)";
           $pat = "/=([0-9A-F]{2})/"; 
           $cha="'.chr(hexdec(";
       # erase null signs in string
          $str=eregi_replace($err,"",$str);
       # to decode with eval and replace
          eval("\$str='".
                  preg_replace($pat,$cha."'$1')).'",$str)
                  ."';");
        # return
           return $str;
} 
#Note: you can to reduce this script in 3 lines.