Commands linked to pg_wrapper not working with non-root users

Hi,

I'm using multiples versions of PostgreSQL from the postgresql.org
repository (http://apt.postgresql.org/) on Debian Jessie, on multiples
servers.
Each postgresql-client-XX package depends on postgresql-client-common,
which provides the pg_wrapper script
(/usr/share/postgresql-common/pg_wrapper).

A lot of PostgreSQL commands are linked to pg_wrapper. E.g.:
/usr/bin/psql -> ../share/postgresql-common/pg_wrapper

Here's my issue : when I'm logged as an user which is not root or
postgresql, I can't use any of the commands linked to pg_wrapper:

user1(at)server1:~ $ /usr/bin/psql --version
Error: Invalid data directory

However, everything works with postgres or root user:

root(at)server1:~ # /usr/bin/psql --version
psql (PostgreSQL) 9.4.16

Also, everything works fine if I bypass pg_wrapper:

user1(at)server1:~ $ /usr/lib/postgresql/9.4/bin/psql --version
psql (PostgreSQL) 9.4.16

I am missing something ?

Thanks,

--
Jonathan Leroy