Sorry to bother you again, but I've tested this not only with Fluentd, but with a RSYSLOG server and it does not work with TCP except if you manually add the trailer LF character. Other than that, UDP default transport protocol has no issues and works fine with both systems. Here's my simple code:

-------
sHandler = logging.handlers.SysLogHandler(address=(address[0], address[1]), socktype = socket.SOCK_STREAM)
sHandler.setFormatter(logging.Formatter(fmt=MSG_SYSLOG_FORMAT, datefmt=DATE_FMT))
self.addHandler(sHandler)
-------

After reading RFC 6587 I think the SyslogHandler class should implement at least one of the framing mechanisms proposed by this RFC, meant for TCP transmission:
- Octet counting
- Trailer character (e.g. LF)

Besides, I've being checking out the library "pyloggr" (https://github.com/stephane-martin/pyloggr) and they are implementing both mechanisms. As for SyslogHandler, it will be as simple as adding another field to the class constructor (use_delimiter?) and to add these lines to the emit code (it works):

-------
if (self.use_delimiter):
    msg = msg + '\n'
else:
    msg = str(len(msg)) + ' ' + msg # default behavior
-------

Thank you again