How do I drop a user having queue tables?

On removing the queue tables using

execute dbms_aqadm.drop_queue_table('AQ$__FT_Q_BEIN_I',true);

gives the following error
ERROR at line 1:
ORA-24002: QUEUE_TABLE DEMO61.AQ$__FT_Q_BEIN_I does not exist
ORA-06512: at "SYS.DBMS_AQADM_SYS", line 2955
ORA-06512: at "SYS.DBMS_AQADM", line 197
ORA-06512: at line 1

There is no entry for this queue table in user_queue_tables but there is an entry for it in user_tables. Can someone help??