Strange CREATE VIEW behavior??

test=# create table zz(ss int, ff varchar);
test=# create view ff2 as select ff as user, ss as num from zz;
test=# create view ff3 as select ff as user1, ss as num from zz;
test=# \d ff2
View "ff2"
Attribute | Type | Modifier
-----------+-------------------+----------
user | character varying |
num | integer |
View definition: SELECT zz.ff AS "user", zz.ss AS num FROM zz;

test=# \d ff3
View "ff3"
Attribute | Type | Modifier
-----------+-------------------+----------
user1 | character varying |
num | integer |
View definition: SELECT zz.ff AS user1, zz.ss AS num FROM zz;

Why in the first case column has name "user" (with '"') ?

PostgreSQL 7.1.2 builded gcc 2.95.3 with options:
./configure --prefix=/usr --sysconfdir=/etc --enable-locale --enable-multibyte=KOI8 --enable-unicode-conversion
--with-tcl --with-perl --with-python --with-openssl --with-CXX --with-gnu-ld --enable-syslog

Linux-2.2.19 on i686, glibc-2.1.3