How do you change the supervisor's password after the initial setup?

There are a few access points for changing this parameter: HTTP, TELNET, and Locally you can alter the Password.
HTTP ->Go to the Configuration Section, Click on "Server Config..."
TELNET ->Log in as supervisor and go to "Configuration.." and select "Server Setup", then select "General Setup".
Local on a console ->Press F2 and select "Server Information".

Under all these options you will see a field that pertains to the Supervisor Password.