code: public PostmarkResponse sendMessage(String from, String to, String replyTo, String cc, String bcc, String subject, String body, boolean isHTML, String tag, List<NameValuePair> headers) throws PostmarkException {
          PostmarkMessage message = new PostmarkMessage(from, to, replyTo, subject, bcc, cc, body, isHTML, tag, headers);
          return sendMessage(message);
      }
docs: Sends a message through the Postmark API.
  All email addresses must be valid, and the sender must be
  a valid sender signature according to Postmark. To obtain a valid
  sender signature, log in to Postmark and navigate to:
  http://postmarkapp.com/signatures.
  
  @param from    An email address for a sender
  @param to      An email address for a recipient
  @param replyTo An email address for the reply-to
  @param cc      An email address for CC
  @param bcc     An email address for BCC
  @param subject The message subject line
  @param body    The message body
  @param isHTML  Is the body text HTML
  @param tag     A tag to identify the message in postmark
  @param headers A collection of additional mail headers to send with the message
  @return {@link PostmarkResponse} with details about the transaction
  @throws PostmarkException when something goes wrong