When a timeout is set on a connected socket, the
socket's send() method behaves as if non-blocking mode
was set: when not enough buffer space is available, it
raises socket.error(10035, 'The socket operation could
not complete without blocking'). Instead, it should
block up to the specified number of seconds and only
then raise a socket.timeout exception if the data still
wasn't sent. This is with Python 2.3.2-1 on Windows 98.
On Linux, it works as expected.

Bug 805194 might be related.