PL/SQL :: XML Errors While Partitioning Existing Table By DBMS_REDEFNITION

I am trying to partition an existing table through DBMS_REDEFNITION. Following are the steps that I have taken and the error I have got.

1. Creating a table to be partitioned.

CREATE TABLE SO33070_ORIGINAL
(
SERIAL_ID NUMBER(15,0),
INSERTED_TIME DATE DEFAULT SYSDATE,
PRIMARY KEY (SERIAL_ID)
);

Success

2. Checking if the table can be partitioned

DECLARE
v_name VARCHAR2(256);
BEGIN
SELECT sys_context('userenv', 'current_user') INTO v_name FROM dual;
DBMS_REDEFINITION.CAN_REDEF_TABLE(v_name, 'SO33070_ORIGINAL', dbms_redefinition.CONS_USE_ROWID);
END;

Success

3. Creating a duplicate table

CREATE TABLE SO33070_NEW
(
SERIAL_ID NUMBER(15,0),
INSERTED_TIME DATE DEFAULT SYSDATE
)
PARTITION BY RANGE ("INSERTED_TIME") INTERVAL (NUMTODSINTERVAL(1,'DAY'))
(
PARTITION "p1_1" VALUES LESS THAN (TO_DATE(' 2012-01-01 00:00:00', 'SYYYY-MM-DD HH24:MI:SS', 'NLS_CALENDAR=GREGORIAN'))
)

Success

4. Starting the redefnition process

EXEC DBMS_REDEFINITION.START_REDEF_TABLE( uname => 'CDS_USER', orig_table => 'SO33070_ORIGINAL', int_table => 'SO33070_NEW', col_mapping => '', options_flag => DBMS_REDEFINITION.CONS_USE_ROWID);
Success

5. Copying the dependents

DECLARE
num_errors NUMBER;
BEGIN
DBMS_REDEFINITION.COPY_TABLE_DEPENDENTS(
uname => 'CDS_USER',
orig_table=>'SO33070_ORIGINAL',
[code]....