there are several ways you can do this.
return a custom bean object that contains both properties and use the axis bean serializer/deserializer
define a, b as in/out parameters and use holder classes
How would you solve this problem in plain java? I don't think this is ws specific.
Thanks for your answer, but I have solved in another way. I have put both the elements in a Vector, and the Client has received a SOAP_VECTOR.