I have product components which contain a mixture of fields, some of which are translated (by Translation Manager/World Server) and some not (like product SKU). Sometimes, the non-translated fields are changed in the localized components (for example a SKU variant for a particular localization), however if the component is re-sent for translation, these changes are lost - the component ends up with the translated fields, plus the original SKU from the parent component.
Is this "just the way it works" with Translation Manager, or is there some way to protect non-translated fields from being wiped on re-translation?