If I use web-services I'm supposing that you don't know nothing about the client and viceversa except for the WSDL.
You may be tempted to add behavior to your generated classes, that won't be shown in the WSDL.
A client that use your jar will have this behaviour added, but for example a .NET client won't know anything about that.
So probably I will just use two different jars, and make sure that the client is just the WSDL mapped classes.
Hope it helps