Vista - converting of class

Im working on a big system. The business logic must be accessable for
several different communication ways. ex web service, RPC etc. It is
supose to be a framework where different communication modules can be
implimented by different persons.
I have designed an interface for the logic modules, where the input and
output is done through reply and request objects. These object is
native c# classes

Each communication type is located in its own module, and must take
care of the communication with its clients, and call the main
module,using the main modules data types.

Client (WS)-> WSService - > Common interface busineslogic

One of the communication clients use a WCF service.

The data comming in to the service and going on to the main module is
the same, except that they are in different namespaces, and the WCF
class contain a datacontract.

I don't want to use the Datacontract class inside the main module,
because its data should be completly independing of the communication
module, and the programmer should have there own way to communicate the
data.
sample classes

using System.Runtime.Serialization;

namespace namespace1 {
[DataContract]
class testClass {
[DataMember]
private string testString;

public string TestString {
get { return testString; }
set { testString=value; }
}
}
}

namespace namespace2 {
class testClass {
private string testString;
public string TestString {
get { return testString; }
set { testString=value; }
}
}
}


i would like to do this

namespace1.testClass t1 = new namespace1.testClass();
namespace2.testClass t2 = new namespace2.testClass();

t1 = t2;
Typecasting don't work.
The question is.. is there an way that i can transfer the data form one
class to another without having to manually transfering each property
of the class?. The structure of each class is exactly the same.