Error of dump OID datatype

Dear sir 
    I use postgres 7.0.3 non-commercial version. I have some error will report about OID datatype bug/error. The problem is I can not export file(OID datatype-text file) from table that was dumped by old database which I backup after it was transfered from old server to new server. 

    Well, When I use command such as
"testDB=#SELECT lo_export(history.file,'/usr/local/etc/webscan/output/aaa') from history where login = 'chong' and ip='202.0.0' and s_date='2001-02-06';"

result is :
ERROR:  Relation 22369 does not exist
    What does it mean?

Thank you