+ * @param Message $message Message object to send
+ * @param resource $stream Handle to the SMTP stream
+ * (when FALSE, nothing will be
+ * written to the stream; this can
+ * be used to determine the actual
+ * number of bytes that will be
+ * written to the stream)
+ * @param string $reply_id Identifies message being replied to
+ * (OPTIONAL; caller should ONLY specify
+ * a value for this when the message
+ * being sent is a reply)
+ * @param string $reply_ent_id Identifies message being replied to
+ * in the case it was an embedded/attached
+ * message inside another (OPTIONAL; caller
+ * should ONLY specify a value for this
+ * when the message being sent is a reply)
+ * @param mixed $extra Any implementation-specific variables
+ * can be passed in here and used in
+ * an overloaded version of this method
+ * if needed.
+ *
+ * @return array An array containing at least these elements in this order:
+ * - The number of bytes written (or that would have been
+ * written) to the output stream
+ * - The message ID (WARNING: if $stream is FALSE, this
+ * may not be supplied, or may not be accurate)