Salesforce adds fields to org.apache.camel.component.salesforce.api.dto.RestResources even after an API has been released. This needs to be handled in the component by ignoring unknown properties for that type.
XStream doesn't support doing this for an single DTO, but it can be done for all types by using XStream.ignoreUknownProperties(). It will make it ignore all unknown properties for all inbuilt DTOs as wells user generated ones. But since the XML payload is less popular, hopefully this behavior won't be an issue.