In Pine 3.90, and later versions, you customize your headers using
the customized-hdrs variable.  Here are instructions for setting your
Organization header.

1. From the Main Menu type S for Setup
2. Type C for Configuration
3. To change the value of the customized-hdrs variable:
   a) Space bar and arrow down to the customized-hdrs variable.
   b) Type A for Add Value
   c) At the prompt type: 

          Organization: Your Organization Name

      If you have set the ORGANIZATION environment variable
      (which is described in 4.2.1 above) you can type: 

          Organization: $ORGANIZATION


While reading a message that you've received you can view all the
headers of the message by typing H.  If H does not work you need to
go to your configuration menu and set the enable-full-header-cmd
variable.

While composing a message you can view all the headers by placing the cursor
in the header region and typing ^R (view rich headers).

NOTE: The customized-hdrs variable is not available in Pine 3.89 and below.