Linux folders permission - postgresql

Hi;
I've got my data base in /var/lib/pgsql/data.
And in the booting of Linux appears a message:
su: atención. No se puede cambiar a /var/lib/pgsql, permiso denegado

(su: attention. We can't change to /var/lib/pgsql, denied permission)

The server belongs to a user named 'Javier'. And the permissión of
/var/lib/pgsql are:

drwxrwx--- 5 javier postgres 1024 dic 10 18:38 pgsql/

(javier and everybody in the group postgres have full access; and my root
belongs also to postgres group)

Please; can any of you tell me if these permissión are good option and why
I've got that message?

Thanks and regards,

Javier