VoiceOne gives you the ability to install and compleatly configure a pbx platform based on Asterisk 1.8 with an easy to use web GUI, which would be a framework to build a communication server adding various plugins.
OpenSubsystems is set of business components such as security, search, inventory management, able to run on various J2EE servers or just using JVM thanks to unique middleware abstraction layer and repository of common application functionality patterns