How can Gnus be configured with multiple NNTP servers?

[Benjamin L. Russell]

I am using Gnus v5.13 on GNU Emacs 23.2.1 on Windows XP Professional,
Service Pack 3, and wish to configure Gnus to use multiple NNTP servers.

I need to set up Gnus to use the following three NNTP servers:

> news20.forteinc.com
> news.gmane.org
> news.gnus.org

Of these three, news20.forteinc.com requires a username and password,
which I have set up on my ~/.authinfo file, as follows:

> machine news20.forteinc.com login <username> password <password>

(In the above line, <username> and <password> are substituted with the
required credentials.)

The other two NNTP servers do not require a username or password.

Currently, I have the following setup in my ~/.gnus.el file:

(setq gnus-select-method '(nntp "news20.forteinc.com"))

(add-to-list 'gnus-secondary-select-methods '(nntp "news.gmane.org"))

(add-to-list 'gnus-secondary-select-methods '(nntp "news.gnus.org"))

For some reason, I am able to subscribe to new newsgroups successfully
using the "Describe all groups" function only in the first two servers,
but not in the third.

The second invocation to (add-to-list 'gnus-secondary-select-methods
...)) seems to be ignored.

How can I specify a third NNTP server in my ~/.gnus.el file?

-- Benjamin L. Russell
-- 
Benjamin L. Russell  /   DekuDekuplex at Yahoo dot com
http://dekudekuplex.wordpress.com/
Translator/Interpreter / Mobile:  +011 81 90-6526-1406
"Furuike ya, kawazu tobikomu mizu no oto." -- Matsuo Basho^