Working (to 1.81.57.73)

debug1: Connection to port 1521 forwarding to 1.81.57.73 port 1521 requested.
debug2: fd 8 setting TCP_NODELAY
debug1: fd 8 setting O_NONBLOCK
debug2: fd 8 is O_NONBLOCK
debug1: channel 2: new [direct-tcpip]
debug1: channel 2: open confirm rwindow 131072 rmax 32768
debug1: channel 2: read<=0 rfd 8 len 0
debug1: channel 2: read failed
debug1: channel 2: close_read
debug1: channel 2: input open -> drain
debug1: channel 2: ibuf empty
debug1: channel 2: send eof
debug1: channel 2: input drain -> closed
debug1: channel 2: rcvd eof
debug1: channel 2: output open -> drain
debug1: channel 2: obuf empty

Non-Working (to 1.81.57.80)

debug1: Connection to port 1521 forwarding to 1.81.57.80 port 1521 requested.
debug2: fd 8 setting TCP_NODELAY
debug1: fd 8 setting O_NONBLOCK
debug2: fd 8 is O_NONBLOCK
debug1: channel 2: new [direct-tcpip]
channel 2: open failed: administratively prohibited: open failed
debug1: channel_free: channel 2: direct-tcpip: listening port 1521 for 1.81.57.8
0 port 1521, connect from 127.0.0.1 port 41932, nchannels 3
debug1: channel 1: rcvd eof
debug1: channel 1: output open -> drain
debug1: channel 1: obuf empty
debug1: channel 1: close_write
debug1: channel 1: output drain -> closed