Well, I wasn’t imagining that I saw it.
Here’s a link where someone else asks about the same thing.
http://uk.answers.yahoo.com/question/index?qid=20100307165541AAQwUMz
I know it’s not much better than wikipedia, but it’s the best I could do with a google search for now.
I’ve looked and can’t find anything that supports that, or that supports Japan by itself being close to creating a nuclear bomb during WW2. There is historical evidence that Germany was close, however.