Solve the pg_dump version mismatch error

After updating postgresql, the server runs on the latest version, 9.2.0.
Whilst, pg_dump in /usr/bin remains on version 9.1.4.

To solve this problem. Remove /usr/bin/pg_dump and create symbolic link
to new pg_dump in /usr/local/bin/pg_dump.

i.e. $ sudo ln -s /usr/local/bin/pg_dump /usr/bin/pg_dump

Done.