Quoting from the Virtual Iron official announcement:
Virtual Iron Software, a provider of server virtualization and virtual infrastructure management software solutions, and Reflex Security, Inc. (www.reflexsecurity.com), an innovator in network intrusion prevention, today announced a partnership to deliver Reflex Security’s Reflex Virtual Security Appliance (VSA) specifically designed for Virtual Iron’s virtual infrastructure environment.
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General availability of the joint Virtual Iron/Reflex Security virtual appliance is planned for Q2, 2007. It will be available for free via download on Virtual Iron’s Virtual Appliance Exchange and at Reflex Security’s website…
This is the first time a virtual appliance is bundled directly with a virtualization platform. In a near future, just like today is a common practice with Linux distribution, virtualization vendors may push several virtual appliances in their installation media, to provide customers a quick startup for their infrastructures.