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In many cases, CXF can run without an SAAJ implementation. However, some features such as JAX-WS handlers and WS-Security do require an SAAJ implementation. By default, CXF ships with the Sun SAAJ implementation, but CXF also supports axis2-saaj version 1.4.1 as an alternative. When using a Java6 JRE, CXF can also use the SAAJ implementation built into Java.
What's the difference between Apache CXF and Fuse Services Framework?
Fuse Services Framework is a certified distribution of Apache CXF provided by FuseSource. FuseSource does all of its development and bug fixes as part of the Apache CXF community, so there are no functional differences between the two. FuseSource may do more frequent releases than Apache, so it is possible to get bug fixes from a Fuse Services Framework release sooner than from an official Apache CXF release.
Consider what Red Hat has done with Linux. Anyone can build their own Linux distribution (http://www.linuxfromscratch.org/) but few people care to do this because of the effort involved in the maintenance, support, testing, validation, etc. of such an effort. Red Hat provides the world with an easily installable Linux distribution with much value added and enterprise level services and support. FuseSource is very similar to Red Hat Linux insomuch as adding value to quality open source software (Apache ActiveMQ, Apache Camel, Apache Derby, Apache ServiceMix, Jetty, etc.) and providing services, support and training for a vetted version of the software.
Are there commercial offerings of CXF that provide services, support, and additional features?
Several companies provide services, training, documentation, support, etc... on top of CXF. Some of those companies also produce products that are either based on Apache CXF or include Apache CXF. See the Support page for a list of companies and the services they provideFor some additional insight into the FuseSource model and how it works, see Bruce Snyder's blog entry entitled The IONA FUSE Model and It's Benefits to the Community. You can also find additional information about Fuse Services Framework and the FuseSource community at "Why join our community".
Is there an Apache CXF certification program?
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