Getting "getsockopt(TCP_KEEPALIVE) failed" LOG message in PG Logs on Solaris 10

I am getting "getsockopt(TCP_KEEPALIVE) failed: Option not supported by protocol" log message in the PG Logs whenever I run a query referencing "pg_catalog.pg_settings" on Solaris 10 (both Sprac and x86-64).

You can reproduce this case by running a query like: SELECT name, setting, unit FROM pg_catalog.pg_settings;

This happens only the first time you execute the query though.

This issue was reproducible to me on both PostgreSQL 9.0.4 and PostgreSQL 9.2.4. This happens when I run the query via psql or pgAdminIII by connecting to the database server over the TCP socket (i.e. by providing host details in -h). Same behavior is not reproducible if I connect to database server over Unix Socket.

I am not sure if this has been reported before, but I thought I should bring this issue to your notice.