Encrypting the admin password is discussed in Managing Security of Passwords. Encrypting the admin password is strongly encouraged. If you want to change the admin password before encrypting it, use the asadmin set command. An example of using the set command for this purpose is as follows:
asadmin set --user admin server.jms-service.jms-host.default_JMS_host.admin-password=new_pwd |
Consult the Admin Console online help for instructions on changing the admin password using the Admin Console.