I use TestNG and RestTemplate for Restful services and although I've never had to implement a soap service I suspect TestNG with WebServiceTemplate would work as well.
TestNG integrates really well with Spring.
For Example( Right out of my current project):
Code:
@ContextConfiguration(locations = {"classpath:/merchant-manager-context.xml","classpath:/merchant-manager-context-test.xml"})
public class ProductDaoIT extends AbstractTransactionalTestNGSpringContextTests {
...snip...
}
That gives you the ability to load your spring configurations and use them in your tests. The test above is an integration test that is only testing two parts of my layered architecture namely: the service layer and the dao layer. However your functional test would likely need to make use of datasources and other things which could be in your spring test xml file like my merchant-manager-context-test.xml.
I realize this isn't very detailed....but hopefully helps a little.