Converting varchar2(512) to RAW(512)

Hi gurus

I need to convert column with a datatype varchar2(512) to a RAW(512) datatype. It seems most people want to do the opposite. Is there a
standard PLSQL or SQL function in Oracle 9i to convert ?

Thanks in advance
Mark

SQL> create table testtable (id number,name varchar2(512));

Table created.

SQL> insert into testtable values (1,'firestorm');

1 row created.

SQL> commit;

Commit complete.

SQL> alter table testtable add nameraw raw(512);

Table altered.

SQL> update testtable set nameraw=utl_raw.cast_to_raw(name);

1 row updated.

SQL> commit;

Commit complete.
SQL> alter table testtable drop column name;

Table altered.