Problems monitoring DB activity - Mailing list pgsql-admin

Hello,

When I do the following:

SELECT * FROM pg_catalog.pg_stat_activity;

The current_query and query_start columns are always empty. Obviously
this makes it hard to monitor problems with the various admin tools, etc.

I'm guessing there's a setting or something that needs updated, I just
need a point in the right direction. DB is 7.4.2

Thanks