oracle数据库，expdp导出时报错

oracle数据库，expdp导出时报错，请问是什么原因呢

Export: Release 11.2.0.1.0 - Production on Thu Jun 18 21:15:04 2015

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;;;
Connected to: Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
;;; Legacy Mode Active due to the following parameters:
;;; Legacy Mode Parameter: "log=xa.log" Location: Command Line, Replaced with: "logfile=xa.log"
;;; Legacy Mode has set reuse_dumpfiles=true parameter.
Starting "XA"."SYS_EXPORT_SCHEMA_15": xa/******** schemas=xa directory=eas_expdata_nfsbackup dumpfile=xa.dmp logfile=xa.log exclude=TABLE:like'VT%' content=all reuse_dumpfiles=true
Estimate in progress using BLOCKS method...
Processing object type SCHEMA_EXPORT/TABLE/TABLE_DATA
Total estimation using BLOCKS method: 66.89 GB
Processing object type SCHEMA_EXPORT/USER
Processing object type SCHEMA_EXPORT/SYSTEM_GRANT
Processing object type SCHEMA_EXPORT/ROLE_GRANT
Processing object type SCHEMA_EXPORT/DEFAULT_ROLE
Processing object type SCHEMA_EXPORT/PRE_SCHEMA/PROCACT_SCHEMA
Processing object type SCHEMA_EXPORT/SEQUENCE/SEQUENCE
Processing object type SCHEMA_EXPORT/TABLE/TABLE
Processing object type SCHEMA_EXPORT/TABLE/GRANT/OWNER_GRANT/OBJECT_GRANT
Processing object type SCHEMA_EXPORT/TABLE/INDEX/INDEX
Processing object type SCHEMA_EXPORT/TABLE/CONSTRAINT/CONSTRAINT
Processing object type SCHEMA_EXPORT/TABLE/INDEX/STATISTICS/INDEX_STATISTICS
Processing object type SCHEMA_EXPORT/TABLE/COMMENT
Processing object type SCHEMA_EXPORT/FUNCTION/FUNCTION
Processing object type SCHEMA_EXPORT/PROCEDURE/PROCEDURE
Processing object type SCHEMA_EXPORT/FUNCTION/ALTER_FUNCTION
Processing object type SCHEMA_EXPORT/PROCEDURE/ALTER_PROCEDURE
Processing object type SCHEMA_EXPORT/VIEW/VIEW
Processing object type SCHEMA_EXPORT/VIEW/GRANT/OWNER_GRANT/OBJECT_GRANT
ORA-39126: Worker unexpected fatal error in KUPW$WORKER.UNLOAD_METADATA [OBJECT_GRANT:"XA"]
ORA-04063: package body "XDB.DBMS_XDBUTIL_INT" has errors
ORA-06512: at "SYS.DBMS_SYS_ERROR", line 95
ORA-06512: at "SYS.KUPW$WORKER", line 8164
----- PL/SQL Call Stack -----
object line object
handle number name
7000004f1a8ef28 19028 package body SYS.KUPW$WORKER
7000004f1a8ef28 8191 package body SYS.KUPW$WORKER
7000004f1a8ef28 2814 package body SYS.KUPW$WORKER
7000004f1a8ef28 8846 package body SYS.KUPW$WORKER
7000004f1a8ef28 1651 package body SYS.KUPW$WORKER
7000005b28136e0 2 anonymous block
Job "XA"."SYS_EXPORT_SCHEMA_15" stopped due to fatal error at 21:24:10