Had a problem with pg_clog

Hi List,

I had a database with a 8 Mb pg_dump file with 1.7 Gb in PG_DATA.

I dropped the database and tried to recreate the db with this
step:

psql template1 < data.sql

All tables and all data was restored and to help accessing the db
I tried to vacuum analyze it, yielding this error message:

vacuumdb -z miwabar
PANIC: open of /var/lib/pgsql/data/pg_clog/0000 failed:
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server closed the connection unexpectedly
This probably means the server terminated abnormally
before or while processing the request.
connection to server was lost
vacuumdb: vacuum miwabar failed

The panic message with -v gave
PANIC: read of clog file 0, offset 16384 failed: Erfolg

which lead me to the mailing-list archive and the following fix:

dd bs=32k count=1 </dev/zero >/var/lib/pgsql/data/pg_clog/0000
1+0 records in
1+0 records out

afterwards my vacuum works.

Had I done the right thing?

Should I have expected this error?

--
Peter