EL Exception Handling block and WCF custom Service Fault Exception

I am currently working on a project to integrate WCF custom fault along with enterprise library exception block.

I was following Guy Burstein's blog for doing this :

http://blogs.microsoft.co.il/blogs/bursteg/archive/2007/04/07/Shielding-WCF-Services-with-Exception-Handling-Application-Block-_2D00_-Part-1.aspx

This example only shows mapping for message and id. The message is of string data type and id is Guid data type.

But what if I have some other custom fields in my custom Fault object in which I have a CategoryID of type string to which I need to map the id of type Guid ?

When I try to do the mapping and propogate it, I get the value as null. Is there some way I could convert the Guid to string type while doing the mapping in EL?

[DataContract]

public class ServiceFault

{

private string categoryCode;

private string message;

[DataMember]

public string CategoryCode

{

get { return categoryCode; }

set { categoryCode = value; }

}

[DataMember]

public string MessageText

{

get { return message; }

set { message = value; }

}

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