I had a dead mirror in my make.conf, so portage downloaded the file directly from SRC_URI, but fails then because of different size (!!! Got: 39391566 !!! Expected: 39391451) Seems like go-oo.org did change that file without changing the versioning. Maybe you can update Manifest and the file on the mirrors to follow them (after testing)?
*** Bug 258678 has been marked as a duplicate of this bug. ***
Indeed, looks like the packages changed upstream :( I've updated the Manifest file now (new sources compile fine here)