JWS 2.1 vs JWS 2.0
JWS (Java Web Services) 2.1 updates JAXB and JAX-WS to 2.1 and adds WSIT to its basic layer. Now JWS 2.1 is supported by GlassFish v2 while JWS 2.0 is built in JDK 6.
One typical issue is definitely how to use JWS 2.1 on JDK 6. It's well known that you can rely on Standard Endorsed Mechanism provided by Java SE, how about updating JWS from 2.0 to 2.1 for JDK 6u1? Comparing with WCF from .NET Framework 3.0, JDK 6 doesn't support WS-* by default. JDK 7 may be a solution, but it will take long.