Iuri,
Take a look at /var/run/postgresql directory and see if Unix domain socket file .s.PGSQL.5432 is there. If not, try /tmp. Maybe a symlink could resolve this issue (ln -s /tmp/.s.PGSQL.5432 /var/run/postgresql/)
Anyway, it seems nspostgres was compiled with another postgresql version instead this running version you describe. See that aolserver could not locate unix domain socket file from nspostgres driver info at service startup.
Try compile nspostgres again and be sure you are running it against your running aolserver and postgresql version.