Hi Mark,
I have tried with the java mapping provided by you and its get worked as per requirement..
Thanks alot for the response 
.
The problem is, the input structure is static and the data present in the "Data" field is dynamic.
The output XML structure is getting generated with the data present in the "Data" field properly as per the provided screenshot.
I cant send the same output different XMl structures to ECC as there should be fixed structure in the proxy to be written.
Could you please provide me the code which will create the Message Type with the namespace, so that i can use the same in the next message mapping after the java mapping and do the necessary modifications.
Regards,
Chaitanya