EDIT

Currently only a few multi-language attributes are really supported by the Editor. These are TextData.multilanguageText and TaxonNode.excludedNote. A similar implementation also exists for term representations.

Not yet implemented is:

TaxonInteraction.description
IndividualsAssociation.descritpion
DescriptionElementBase.modifyingText
KeyStatement.label
StateData.modifyingText
Media.title
Media.description
SpecimenOrObservationBase.definition
Classification.description

Some of them are even not yet implemented as simple fields.

On model side we should also check if it is not possible now to use the existing eu.etaxonomy.cdm.model.common.MultilanguageText class. Long time ago hibernate did not support this due to a hibernate bug or missing feature.

See alos #9007#note-11 (or related follow-up ticket)