Hi,
As framework considers the conversion exits defined for attributes and accordingly the conversion exits been applied while rendering view. Either you need to remove the conversion exits from domain if any or you need to create similar domain without any conversion exit.
I agree that your requirement specification referring to particular fields/domains but to achieve your requirement you need to do as suggested above. Still fetch/save data from/to same fields but in Webdynpro context you have different domains without any conversion exits for the affected fields.
Regards,
Rama