export fails with EXP-00008 ora-6550

EXP-00008: ORACLE error 6550 encountered

ORA-06512: at "SYS.DBMS_EXPORT_EXTENSION", line 97

ORA-06512: at "SYS.DBMS_EXPORT_EXTENSION", line 126

EXP-00008: ORACLE error 6510 encountered

ORA-06512: at "SYS.DBMS_EXPORT_EXTENSION", line 50

ORA-06512: at "SYS.DBMS_EXPORT_EXTENSION", line 126

EXP-00008: ORACLE error 6550 encountered

. . exporting table    CWM2$OLAPEXPORTCOMMANDTABLE

. . exporting table     CWM2$OLAPEXPORTOBJECTTABLE

. about to export LAB6EXP's tables via Conventional Path ...

GRANT EXECUTE ON SYS.DBMS_DEFER_IMPORT_INTERNAL TO ;
GRANT EXECUTE ON SYS.DBMS_EXPORT_EXTENSION TO ;