nodeRead: did not find '}' at end of plan node

Dear All:
Im running psql (PostgreSQL) 7.3.2 here and since some weeks Im getting this error when trying to dump all databases
(toupgrade to pg 7.4.1) 

\connect XXX
pg_dump: SQL command failed
pg_dump: Error message from server: ERROR:  nodeRead: did not find '}' at end of plan node
pg_dump: The command was: select (select usename from pg_user where usesysid = datdba) as dba, encoding, datpath from
pg_databasewhere datname = 'emepe3' 
pg_dumpall: pg_dump failed on emepe3, exiting


I've found some pages in google but I couldn't find the answer.

Thanks in advance!

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