There are many GREAT resources on the Internet. One I (re)discovered the other day is http://dicts.info. It provides information for some 79 languages and the information they provide is Freely licensed; the data can be downloaded for personal use as it can change rapidly.
So how do we integrate such information in WiktionaryZ ? WiktionaryZ insists on the concept of the DefinedMeaning. As this is central to how WiktionaryZ works, it is crucial that we have the concept defined. The dicts.info is split into two parts; a from part and a to part. The translations include synonyms and alternate spellings.
An application that is to include these translations could work like this: When an Expression is found in the to language and the translation is not there already, a user is shown the WiktionaryZ content with the suggestion to add the translation. This way the new information is integrated into WiktionaryZ.
The one part of this "how to" needed is possibly some discussion on the finer details, but certainly someone who will take up this challenge and develop this for us.