in postgresql BLOB type (that is),question about oid type?

hi..
in postgresql db,
i used oid type for inserting big file size in database.
but i have error like below....

error contents;
==============
FastPath call returned ERROR: pg_attribute_relid_attnam_index: cannot
extend.
Check free disk space.

at org.postgresql.fastpath.Fastpath.fastpath(Unknown Source)
at org.postgresql.fastpath.Fastpath.fastpath(Unknown Source)
at org.postgresql.fastpath.Fastpath.getInteger(Unknown Source)
at org.postgresql.largeobject.LargeObjectManager.create(Unknown
Source)
at org.postgresql.jdbc2.PreparedStatement.setBinaryStream(Unknown
Source
)
at testlob1.main(testlob1.java:29)
please tell me advice.....
my email address : leeds(at)catholic(dot)or(dot)kr