tcpip_socket parameter in postgresql.conf

Hello,

according to http://www.postgresql.org/docs/7.4/static/runtime-config.html
the parameter tcpip_socket can be used to enable/disable the usage of
TCP/IP connections. From what I have read this can/could replace the -i
switch for the postmaster.

However, when I try this parameter in my postgresql.conf file, I get an
error message upon startup.

FATAL:  unrecognized configuration parameter "tcpip_socket"

Did I miss anything?
Or is this simply not supported by the Win32 version?

I'm using the win32 binaries from May 20th.

Regards
Thomas