Well, yes, SOA-P 5.2 does not include JBWS 4.x, it should have a 3.1.2.SPx release afair.
However, you're declaring a dependency on jbossws-native-client 3.3.1.GA in your pom above, that's why I said there's a mismatch between the 1.1.0.GA plugin and the JBWS version you're using.