WCF ignore namespace of return type

See more:

C#

C#4.0

WCFServices

Hello,

I have a project which I completely redesigned.
Therefore the namespaces of some classes have changed. One of them is the returntype of a WCF-Service.

The older version of my application had a autoupdate function.
The client sended a request to the server, and the response contained a field if the client should update or not.

After recreating the services and changing the namespace of the reponse class (without changing the class at all), all the values of the response have null or empty values.

How can I ignore the namespace of the return value of a service.
I can only change the server side, because the client is allready running on the users machines and can't be changed.

Kind regards.