无法删除dbms_aqadm.drop_queue_表的Oracle队列表

我正在尝试将log4plsql的意外安装清理到错误的(即,sys)模式中。有一个名为 QTAB_LOG 那就得走了。我已成功停止并删除关联队列:

call DBMS_AQADM.STOP_QUEUE('LOG_QUEUE');
call DBMS_AQADM.DROP_QUEUE('LOG_QUEUE');

但删除队列表本身失败:

call DBMS_AQADM.DROP_QUEUE_TABLE('QTAB_LOG');

出现此错误:

SQL Error: ORA-00942: table or view does not exist
ORA-06512: at "SYS.DBMS_AQADM", line 240
ORA-06512: at line 1
00942. 00000 -  "table or view does not exist"

当然,以正常方式放下桌子:

drop table QTAB_LOG;

不允许:

SQL Error: ORA-24005: Inappropriate utilities used to perform DDL on AQ table LOG4PLSQL.QTAB_LOG
24005. 00000 -  "must use DBMS_AQADM.DROP_QUEUE_TABLE to drop queue tables" 
*Cause:    An attempt was made to use the SQL command DROP TABLE for queue
           tables, but DROP TABLE is not supported for queue tables.
*Action:   Use the DBMS_AQADM.DROP_QUEUE_TABLE procedure instead of the
           DROP TABLE command.

我做错什么了?