[rkomar]

Wouldn't the epub be seen as a new publication whose copyright term begins anew? If there are changes in the text from the originally published version, then those would be protected by copyright. I would think that you would have to compare the epub's text against the original text word by word, and revert any changes to the original version. But then again, IANAL.

The gutenberg sites are pretty careful about only using scans from editions that would be out of copyright. They avoid modern reprints that might have modifications to the original text (including fixed typos).