This error is due to the execute grant missing on DBMS_EXPORT_EXTENSION
Error
test*TESTDB1:/home/oracle>exp menu file=export.dmp tables=test_table1 log=export.log
Export: Release 11.2.0.3.0 – Production on Thu May 24 10:46:42 2012
Copyright (c) 1982, 2011, Oracle and/or its affiliates. All rights reserved.
Password:
EXP-00056: ORACLE error 6550 encountered
ORA-06550: line 1, column 15:
PLS-00201: identifier ‘SYS.DBMS_EXPORT_EXTENSION’ must be declared
ORA-06550: line 1, column 15:
PL/SQL: Statement ignored
EXP-00000: Export terminated unsuccessfully
Fix
To get round this error you need to
GRANT EXECUTE ON DBMS_EXPORT_EXTENSION to PUBLIC;
You can now run the export with no errors.