Anyone know how or is there a utility to read / decode materialized view logs?

Here's an example:

************************************************** ****
SQL> describe mlog$_Test1;
Name Null? Type
----------------------------------------- -------- ------------
F1 VARCHAR2(10)
SNAPTIME$$ DATE
DMLTYPE$$ VARCHAR2(1)
OLD_NEW$$ VARCHAR2(1)
CHANGE_VECTOR$$ RAW(255)

SQL> Select * from mlog$_Test1;

F1 SNAPTIME$ D O
---------- --------- - -
CHANGE_VECTOR$$
-----------------------------------
one 01-JAN-00 I N
FE

three 01-JAN-00 I N
FE

three 01-JAN-00 U U
04


F1 SNAPTIME$ D O
---------- --------- - -
CHANGE_VECTOR$$
-----------------------------------
one 01-JAN-00 D O
00
************************************************** **

Everything makes sense; I can tell what the primary key is and if it is an insert, update, or delete; except that the data values must be in the CHANGE_VECTOR$$ field. Is there a way to decode this field?

Appreciate all input