pg_dump/restore problem

I am trying to move some data from an 8.0.7 instance to a 7.4.8
instance. I did a pg_dump and then did a pg_restore.
For the most part the data transferred through to the older instance but
I had problems with the sequence updates.

 SELECT pg_catalog.setval(pg_catalog.pg_get_serial_sequence('nw_foo',
'foo_id'), 678, true);
ERROR:  function pg_catalog.pg_get_serial_sequence("unknown", "unknown")
does not exist
HINT:  No function matches the given name and argument types. You may
need to add explicit type casts.

I am looking for a an alternative to manually issuing alter sequence
commands.

Any help appreciated.