Expdp ORA-31633 ORA-01031 when exporting using userid=/

Hi to all,

we are facing ORA-31633 ORA-01031 when doing  an expdp on a 11.2.0.2.0 Database, using "userid=/":

               expdp userid=/ directory=DATA_PUMP_DTS_PRUEBA tables=DTSPREP.BATCH_RTD_MSG_DAT dumpfile=expdp_batch_rtd_msg_dat.dmp logfile=expdp_batch_rtd_msg_dat.log

Connected to: Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 - 64bit Production

With the Partitioning, Real Application Clusters, Automatic Storage Management, OLAP,

Data Mining and Real Application Testing options

ORA-31626: job does not exist

ORA-31633: unable to create master table "OPS$ORACLE.SYS_EXPORT_TABLE_05"

ORA-06512: at "SYS.DBMS_SYS_ERROR", line 95

ORA-06512: at "SYS.KUPV$FT", line 1020