In camel-tcp-stream-raw.c:socket_connect, connect returns -1 with errno 0. In normal case, connect should return -1 with errno 150. Please refer to the following code:

        int fdmax, status;
        fd_set rdset, wrset;

#ifndef G_OS_WIN32
        flags = fcntl (fd, F_GETFL);
        fcntl (fd, F_SETFL, flags | O_NONBLOCK);
#else
        {
            u_long yes = 1;
            ioctlsocket (fd, FIONBIO, &yes);
        }
#endif
        if (connect (fd, h->ai_addr, h->ai_addrlen) == 0) {
#ifndef G_OS_WIN32
            fcntl (fd, F_SETFL, flags);
#else
            {
                u_long no = 0;
                ioctlsocket (fd, FIONBIO, &no);
            }
#endif
            return fd;
        }

        if (!SOCKET_ERROR_IS_EINPROGRESS ()) {
            errnosav = errno;
            SOCKET_CLOSE (fd);
            errno = errnosav;
            return -1;
        }

This has already been reported as bug 538074, thus marking it as such.

*** This bug has been marked as a duplicate of 538074 ***