BUG #3941: Insert Error

The following bug has been logged online:

Bug reference: 3941
Logged by: gnp yadav
Email address: gnperumal(at)gmail(dot)com
PostgreSQL version: 8.1
Operating system: Ubuntu Linux
Description: Insert Error
Details:

CREATE TABLE sentence
(
sentence_id serial NOT NULL,
citation_id int8 NOT NULL,
sen_offset int8 NOT NULL,
sen_length int8 NOT NULL,
sen_type varchar(10)[] NOT NULL,
CONSTRAINT sentence_id PRIMARY KEY (sentence_id),
CONSTRAINT citation_id FOREIGN KEY (sentence_id)
REFERENCES citation (citation_id) MATCH SIMPLE
ON UPDATE NO ACTION ON DELETE NO ACTION
) ;

INSERT INTO sentence (sentence_id, citation_id, sen_offset, sen_length,
sen_type) VALUES (NULL,1,2,3,asd");

As i Got This type error frequently

ERROR: column "asd" does not exist

please guide me, Advance thanks to for my teacher.