FETCH FORWARD 0 and "cursor can only scan forward" error

Hi,
I'm on PostgreSQL 9.2.2 and trying to use no scroll cursor for some data fetch. But when moving cursor ahead one record and the fetching the actual record the error "cursor can only scan forward" is returned. I don't know if I'm doing something wrong but I don't think I'm going backward with cursor. Here is the code that demonstrate it

BEGIN;

DECLARE CUR_1 NO SCROLL CURSOR WITHOUT HOLD FOR SELECT * FROM GENERATE_SERIES(1, 2);

FETCH FORWARD 0 FROM CUR_1; -- 0

MOVE FORWARD FROM CUR_1;

FETCH FORWARD 0 FROM CUR_1; -- 1

ABORT;

The line marked as "-- 0" is working OK, the line marked as "-- 1" is throwing error:

ERROR:  cursor can only scan forward
HINT:  Declare it with SCROLL option to enable backward scan.

********** Error **********

ERROR: cursor can only scan forward
SQL state: 55000
Hint: Declare it with SCROLL option to enable backward scan.

I want to iterate all records with cursor from beginning to end. This sample could be rewritten using FETCH FORWARD 1 ... without using MOVE but I'm interested with solution which throws error.

Thank you

Trigve