ORA-03113 with DEC3Encrypt

I have the following Stored Procedure, adapted from several examples:

CREATE OR REPLACE PROCEDURE "TEST_ENCRYPT" (input_string in VARCHAR2) as

   input_string2 VARCHAR2(16) :=
RPAD(input_string, 16);

   key_string          		VARCHAR2(16)  := 'scottscottscotts';
   encrypted_string         VARCHAR2(2048);
  

BEGIN
    dbms_obfuscation_toolkit.DES3Encrypt(

               input_string => input_string2, 
               key_string => key_string, 
               encrypted_string => encrypted_string );

      dbms_output.put_line('> encrypted hex value              : ' || 
                   rawtohex(UTL_RAW.CAST_TO_RAW(encrypted_string)));

END;
/

When using Oracle 9i (version 9.2.0.1), this works great.

However, when running in 9.2.0.6 (both Windows) I get: ORA-03113: end-of-file on communication channel

There doesn't appear to be any accompanying error messages. That's the one and only line that displays.

Thanks.

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