Sockets: code works locally but fails over LAN

[n00m]

Thanks, Bryan, for the details!

Btw, the newest oops in the topic's subject is:
the code does not work in the case of:

sqls_host, sqls_port = '192.168.0.8', 1433
proxy_host, proxy_port = '192.168.0.3', 1434
## proxy_host, proxy_port = '127.0.0.1', 1434
## proxy_host, proxy_port = '', 1434

I.e. when both Python and vbs script run on one machine
(with ip = 192.168.0.3) and SQL Server runs on another
(with ip = 192.168.0.8)

How namely it does not work:
in the idle window only one line is printed:

VB_SCRIPT:
.........

that's all. No errors from Python. After timeout expires
I get an error message from VBS (smth like preHandShake()
failed; I've never seen it before).

I just wonder MUST (or not) it work at all (IN THEORY)?

PS: again, without Python vbs and sql server contact with
each other PERFECTLY.