error while vacuuming

I try do vacuum a database:

[PostgreSQL 6.5.0 on i686-pc-linux-gnu, compiled by gcc egcs-2.91.66]

   type \? for help on slash commands
   type \q to quit
   type \g or terminate with semicolon to execute query
 You are currently connected to the database: ecoscan

ecoscan=> vacuum;
ERROR:  Index pg_temp.3920.1 is not a btree

Any hints? Is it possible that the creation of temporary tables with
indexes clashes vacuum?

Thanks Herbie


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Herbert Liechti                            E-Mail: Herbert.Liechti@thinx.ch
ThinX networked business services               Stahlrain 10, CH-5200 Brugg
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