pageoneresults - 5:25 pm on Dec 28, 2006 (gmt 0)

Our website does rank well, however, about a month ago we translated about 30 pages from our website in 3 foreign languages - and all those pages (the translations only) went supplemental.

That is Google's normal behavior in some instances. Supplementals mean many things. In this case, they are new pages that Googlebot has spidered that don't meet a minimum criteria as of yet for pushing them into the main index. Give it some time, they will most likely come out of Supplemental.

Well, it was not worth it.

I think it was. Your visitors didn't appreciate the translations?

I didnt know that Google considers translations a duplicate, even though they are from our own website.

They don't consider translations duplicate. They are treated separately. There are some additional things you can do to make sure that they are. Language headers help to define the page in a particular language.