COPY can t make file

Hello out there,

I've found a somehow strange behaviour of postgreSQL 7.0; consider the
following:

1. user umehlig, in psql:
=========================
db=# COPY blatt TO '/usr/local/tmp/blatt.txt' USING DELIMITERS '|' with null as '';
ERROR: COPY command, running in backend with effective uid 1100,
could not open file '/usr/local/tmp/blatt.txt' for writing. Errno =
Keine Berechtigung (13). -- "Keine Berechtigung": "no permission"

2. user postgres, outside psql:
===============================
[postgres@pandora3 pgsql]$ grep 1100 /etc/passwd
postgres:*:1100:1100:PostgreSQL Super User:/usr/local/pgsql:/bin/sh
[postgres@pandora3 pgsql]$ grep postgres /etc/group
users::100:umehlig,postgres
postgres:*:1100:postgres
[postgres@pandora3 pgsql]$ touch /usr/local/tmp/blatt.txt
[postgres@pandora3 pgsql]$ ls -ld /usr/local/tmp/ /usr/local/tmp/blatt.txt
drwxrwxr-t 3 root users 144 May 29 21:47 /usr/local/tmp/
-rw-rw-r-- 1 postgres postgres 19011 May 29 21:48 /usr/local/tmp/blatt.txt

3. user umehlig, in psql:
=========================
db=# COPY blatt TO '/usr/local/tmp/blatt.txt' USING DELIMITERS '|' with null as '';
COPY

The COPY command does succeed only after manually generating the file
-- is there something wrong with my permissions, or is there something
wrong with the COPY command?

Thanxs,
Ulf

psql (PostgreSQL) 7.0.0
RedHat 6.1/i386, kernel 2.2.14

--
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Ulf Mehlig <ulf.mehlig@zmt.uni-bremen.de>
Center for Tropical Marine Ecology/ZMT, Bremen, Germany
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