protected function decodeHeader()
    {
        if (isset($this->header->subject)) {
            $this->header->subject = $this->mimeHeaderDecode($this->header->subject);
        }
        if (isset($this->header->details->subject)) {
            $this->header->details->subject = $this->mimeHeaderDecode($this->header->details->subject);
        }
        if (isset($this->header->details->Subject)) {
            $this->header->details->Subject = $this->mimeHeaderDecode($this->header->details->Subject);
        }
        if (isset($this->header->from)) {
            $this->header->from = $this->mimeHeaderDecode($this->header->from);
        }
        if (isset($this->header->to)) {
            $this->header->to = $this->mimeHeaderDecode($this->header->to);
        }
    }