How do I set the RT hostname?

I'm in the process of setting up a new RT 4.4 instance. I used the web
installer, which generated the following RT-SiteConfig.pm:

Set( $CommentAddress, '[email protected]' );
Set( $CorrespondAddress, '[email protected]' );
Set( $DatabaseHost, 'localhost' );
Set( $DatabaseName, 'rt4' );
Set( $DatabasePassword, 'xxxxxxxxxxxxx' );
Set( $DatabasePort, '' );
Set( $DatabaseType, 'mysql' );
Set( $DatabaseUser, 'rt_user' );
Set( $Organization, 'rt2.example.com' );
Set( $OwnerEmail, '[email protected]' );
Set( $SendmailPath, '/usr/sbin/sendmail' );
Set( $WebDomain, 'rt2.example.com' );
Set( $WebPort, '80' );
Set( $rtname, 'rt2.example.com' );
1;

{ I've substituted 'rt2.example.com' for the actual FQDN of the machine
that's hosting the instance }

When I tried to set up a new asset, I got the following error message:

RT has detected a possible cross-site request forgery for this request,
because the Referrer header supplied by your browser (rt2.example.com:80)
is not allowed by RT's configured hostname (127.0.0.1:80).

A bit of googling showed me how to set this in  RT-SiteConfig.pm:

Set(@ReferrerWhitelist, qw(127.0.0.1:80));

... that did disable the message, but why is the 'configured hostname' set
to 127.0.0.1:80, and how do I set it to the actual domain name of the
machine?

Thanks,

--Barton

---------
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