Multiple Web Services referencing the same request objects

I have a group of web services, 4 of which have to pass around the same object. I believe, but not sure I am right, that I should have one of the web services define the class, and all the other web services should create a reference to that class.

Now I am presuming that because these will be referenced via a web service, essentially they will be in different namespaces, so I would have to convert them when I want to pass the object on to another web service. But if i didn't do this, and each web service had defined the same class, I开发者_JAVA百科 would have to map the fields, or I could you serialization to convert the objects. But obviously in this instance, if I needed to make a change, I would have to make it to each class in each web service.

Am I right, and is there a better solution? I have a mixture of .NET 2.0 and 3.5 web services. I would ideally just want to take the object in as a parameter and pass it on to another web service as a parameter.