Vacuudb problem

Hi,

Help me please to resolve my problem. It is during vacuuming
database .I resolved it last time in such a way: pg_dump and
psql -e db<db.archiv. But after some days it appeared again.
  Here is messages :

NOTICE:  mdopen: couldn't open pg_temp.2297.4: No such file or directory
NOTICE:  RelationIdBuildRelation: smgropen(pg_temp.2297.4): No such file or directory
NOTICE:  mdopen: couldn't open pg_temp.2297.4: No such file or directory
ERROR:  cannot open relation pg_temp.2297.4
vacuumdb: vacuum failed

And one more question. Is there any way to encrease speed
of restoring database . psql -e works about some hours for me...

Thanks for any suggestions.

Igor