set_curcfg('default') + tsearch1 call = postmaster crash

Greetings,

in my database i have both tsearch1 and tsearch2 .
the following sequence of commands lead to this
repeatble problem .

Any solution ?

Regds
mallah.

Welcome to psql 7.4RC2, the PostgreSQL interactive terminal.

Type: \copyright for distribution terms
\h for help with SQL commands
\? for help on internal slash commands
\g or terminate with semicolon to execute query
\q to quit

tradein_clients=# SELECT version();
version
--------------------------------------------------------------
PostgreSQL 7.4RC2 on i686-pc-linux-gnu, compiled by GCC 2.96
(1 row)

tradein_clients=#
tradein_clients=# SELECT public.set_curcfg('default');
set_curcfg
------------

(1 row)

tradein_clients=# SELECT 'herbal tea'::txtidx ## 'tea|herbal';
server closed the connection unexpectedly
This probably means the server terminated abnormally
before or while processing the request.
The connection to the server was lost. Attempting reset: Failed.
!>
!>