PgSQL 6.5.1 and Group BY pb

Running PostgreSQL-6.5.1 (rpm version distributed for linux on redhat
6.0)

GROUP BY complitely fails

bash$ psql template1
template1=> CREATE TABLE "gruppi" ("id" int4 NOT NULL,"nome" character
varying(32));
CREATE
template1=> CREATE TABLE "usergroup" ("id" int4 NOT NULL,"uid" int4 NOT
NULL,"gid" int4 NOT NULL);
CREATE
template1=> insert into gruppi values (0,'ciao');
INSERT 31637 1
template1=> insert into gruppi values (1,'pippo');
INSERT 31638 1
template1=> insert into usergroup values (0,1,2);
INSERT 31639 1
template1=> insert into usergroup values (0,2,3);
INSERT 31640 1
template1=> insert into usergroup values (1,2,3);
INSERT 31641 1

And now the output query with GROUP BY:

template1=> SELECT g.nome,u.uid,u.id FROM gruppi g, usergroup u GROUP BY
g.nome;
ERROR:  Illegal use of aggregates or non-group column in target list
template1=> SELECT nome,id FROM gruppi GROUP BY nome;
ERROR:  Illegal use of aggregates or non-group column in target list

And now the output query with SELECT DISTINCT:

template1=> SELECT DISTINCT ON g.nome g.nome,u.uid,u.id from gruppi g,
usergroup u;
ERROR:  parser: parse error at or near "."


-- 
Best Regards
----------------------------
Giampiero Raschetti
Sistemi Innovativi
Banca Popolare di Sondrio
----------------------------