oracle - PL SQL output is not getting displayed -

i have code ..running in oracle virtualbox. reason not displaying pl/sql output.

here code snippet

sql> set serveroutput on sql> list     1   create or replace procedure mytz     2           3       v_mytz timestamp time zone default '2013-05-05 12:00:00 am';     4       begin     5       dbms_output.put_line ('default timestamp ' );     6*     end mytz ; sql> /       procedure created.   sql>  

is there need special see output on sql prompt ?

you have run procedure, not create it, e.g.:

set serverputput on exec mytz; 

the set serveroutput sql*plus command has in session procedure executed, not 1 created (if different).

you not showing value of variable @ moment; maybe wanted this?

    dbms_output.put_line('default timestamp is: ' || v_mytz);