Nagios Core 4.0.4 has just been released and can be downloaded from
The major feature in this version is the beta release of the JSON CGIs. For more information about the JSON CGIs, see the presentation from the 2013 Nagios World Conference at http://www.slideshare.net/nagiosinc/eric-stanley-and-andy-brist-api-and-nagios/46.
The full change log is below.
4.0.4 - 03/14/2014
* JSON CGIs moved to beta status (Eric Stanley)
* Fixed bug #491,#553: Rebuilt the daemon-init scripts back to something that should work on all systems (Scott Wilkerson)
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