psql don't conect in debian of a VPS

psql don't conect in debian of a VPS

I in a VPS has a Debian (paravirtual), I run dpkg-reconfigure locales
because not install locales before, I install postgresql 9.1 with apt-get
install postgresql and change to postgres user with su postgres, when run
psql don't conect:
psql: could not connect to server: No such file or directory
Is the server running locally and accepting
connections on Unix domain socket
"/var/run/postgresql/.s.PGSQL.5432"?