seg fault with tsearch2

I have Pg installed on i386 NetBSD from the NetBSD package manager. I
then installed tsearch2 and used its default installation.
I then also got the source and built from it, with debugging enabled.
Again I installed tsearch2 but my results were the same.

Created a new database, added a table with:

CREATE TABLE server_file (
server_file_id serial NOT NULL,
server_id integer NOT NULL,
server_file_path text NOT NULL,
server_file_name text NOT NULL,
server_file_ext character varying(20),
server_file_size integer NOT NULL,
server_file_index tsvector,
protocol_id integer NOT NULL
);

ALTER TABLE ONLY server_file
ADD CONSTRAINT server_file_pkey PRIMARY KEY (server_file_id);

CREATE INDEX server_file_indexindex ON server_file USING gist
(server_file_index);

CREATE TRIGGER tsvectorupdate
BEFORE INSERT OR UPDATE ON server_file
FOR EACH ROW
EXECUTE PROCEDURE tsearch2('server_file_index',
'server_file_name', 'server_file_path');

---------------Query executed:

insert into server_file values (default,'511','/test/20-Shania
Twain-Party For Two with Billy
Curringtonmp3','mp3','323',default,'1');

---------------Output from gdb------------

Program received signal SIGSEGV, Segmentation fault.
0x48b22c84 in find_among () from /usr/pkg/lib/tsearch2.so

#0 0x48b22c84 in find_among () from /usr/pkg/lib/tsearch2.so
#1 0x48b21d02 in ts_stat () from /usr/pkg/lib/tsearch2.so
#2 0x48b21e58 in english_stem () from /usr/pkg/lib/tsearch2.so
#3 0x48b14383 in snb_lexize () from /usr/pkg/lib/tsearch2.so
#4 0x081cdf59 in FunctionCall3 (flinfo=<incomplete type>, arg1=137034080,
arg2=137063728, arg3=11) at fmgr.c:1164
#5 0x48b17bf5 in parsetext_v2 () from /usr/pkg/lib/tsearch2.so
#6 0x48b1a5e4 in tsearch2 () from /usr/pkg/lib/tsearch2.so
#7 0x080f25c7 in ExecCallTriggerFunc (trigdata=0xbfbff670,
finfo=<incomplete type>, per_tuple_context=<incomplete type>)
at trigger.c:1149
#8 0x080f2885 in ExecBRInsertTriggers (estate=<incomplete type>,
relinfo=<incomplete type>, trigtuple=<incomplete type>) at trigger.c:1261
#9 0x081032dd in ExecInsert (slot=<incomplete type>,
tupleid=<incomplete type>, estate=<incomplete type>) at execMain.c:1344
#10 0x08102f9e in ExecutePlan (estate=<incomplete type>,
planstate=<incomplete type>, operation=<incomplete type>, numberTuples=0,
direction=<incomplete type>, dest=<error type>) at execMain.c:1207
#11 0x081023d6 in ExecutorRun (queryDesc=0x8349440,
direction=<incomplete type>, count=0) at execMain.c:226
#12 0x0816d629 in ProcessQuery (parsetree=<error type>, plan=<error type>,
params=<error type>, dest=<error type>, completionTag=0xbfbff910 "")
at pquery.c:173
#13 0x0816e385 in PortalRunMulti (portal=<error type>, dest=<error type>,
altdest=<error type>, completionTag=0xbfbff910 "") at pquery.c:1016
#14 0x0816dd76 in PortalRun (portal=<error type>, count=2147483647,
dest=<error type>, altdest=<error type>, completionTag=0xbfbff910 "")
at pquery.c:617
#15 0x0816a76a in exec_simple_query (query_string=<incomplete type>)
at postgres.c:933
#16 0x0816c979 in PostgresMain (argc=4, argv=<incomplete type>,
username=<incomplete type>) at postgres.c:3007
#17 0x0811b4ed in main (argc=4, argv=<incomplete type>) at main.c:334
#18 0x08072122 in ___start ()