Attachments and comments in the history of an document are not correct

If you create a document add attachments and update the attachments you don't get the right version of the attachment with a revision of the document from history.
You always see the last rev of the attachment in any rev of the document.

If you add an comment and delete it in a newer version of the document you get "Comments (1)" in the old version of the document, but don't see the comment. On the other hand if you add comments to a newer rev of the document and look at a older rev you see "Comments (0)" but there are the comments of the new rev of the document.

Is the same on your own wikifarm, see "User's Guide" as an example...

http://enterprise.xwiki.org/xwiki/bin/viewrev/UserGuide/WebHome?rev=3.1

Question:
Is there a way to get the content from a url with "downloadrev" example
"http://<server>/xwiki/bin/downloadrev/..." without login and
without adminrights?