Catch all domains *and* subdomains?

[Phillip Oldham]

  How can I configure nginx to catch all domains and all subdomains of 
any domains?

Using the following catches all domains, but doesn't seem to catch 
subdomains:

server {
server_name _;
}

Suggestions?
-- 

*Phillip B Oldham*
ActivityHQ
phill at activityhq.com <mailto:phill at theactivitypeople.co.uk>

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