ORA-42012: error occurred while completing the redefinition

An error stack showed up when trying to use the DBMS_REDEFINITION package. After issuing the command

dbms_redefinition.finish_redef_table('MADRID', 'a_table', 'an_int_table', 'a_partition');

The following error stack showed up:

begin
*
ERROR at line 1:
ORA-42012: error occurred while completing the redefinition
ORA-04020: deadlock detected while trying to lock object MADRID.TABLE1_INT
ORA-06512: at "SYS.DBMS_REDEFINITION", line 78
ORA-06512: at "SYS.DBMS_REDEFINITION", line 1680
ORA-06512: at line 2

When I was trying to remove the interim table to restart the redefinition procedure it conflicted with a couple of interim objects created on the fly.

SQL> drop table table1_int;
drop table table1_int
*
ERROR at line 1:
ORA-12083: must use DROP MATERIALIZED VIEW to drop "MADRID"."TABLE1_INT"

SQL> DROP MATERIALIZED VIEW "MADRID"."TABLE1_INT";
Materialized view dropped.

SQL> drop table table1_int;
Table dropped.

This is due to a bug in the 11.2.0 release on every OS platform. This will be fixed in future releases, in the mean time the workaround for this problem is to modify an Oracle Instance parameter, just set the deferred_segment_creation to FALSE and retry the operation.