strange error

hi,
i have relation with 3 int's and 1 text :
\d newstexts
                           Table "newstexts"
 Attribute |  Type   |                    Modifier
-----------+---------+-------------------------------------------------
 id        | integer | not null default nextval('newstexts_seq'::text)
 news_id   | integer | not null default ''
 class_id  | integer | not null default ''
 text      | text    | not null default ''

i also have a rather complicated trigger which does some trick *AFTER*
inserting data to this table.
when i try to insert something i got:
ERROR:  newses_seq.nextval: bad magic (00000000)

i know it's my fault. but what should i look for to trace the problem, and kill
the bug?
i would really appreciate quick answers or suggestions (i'm running out of time
...)

depesz

--
hubert depesz lubaczewski                          http://www.depesz.pl/
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