pg_dump crashes the backend

[7.3.2 on debian unstable]

We recently had an unclean server shutdown and now a pg_dump command
crashes the backend:

pg_dump: PANIC:  open of /var/lib/postgres/data/pg_clog/0003 failed: No
such file or directory

Should we restore from a known good dump after an initdb?

--    PHEDRE: Malheureuse ! Voilà comme tu m'as perdue.           Au jour que je fuyais c'est toi qui m'as rendue.
                                  (Phèdre, J-B Racine, acte 4, scène 6)