Is it OK for a referee to acknowledge identity with a previous referee? As with this older related question, question anonymous for obvious reasons.
If I have been asked to review the same paper twice, is it OK to acknowledge in my review that I am the same person as one of the referees from last time?  I'm sure cryptographers would frown on that sort of thing, but it's not clear that there is actually a practical problem with this.
Thanks!
 A: I've been in this situation with a paper that had significant problems and was submitted to a second journal without addressing any of the comments that I made in my first review.  I explained this to the editor of the second journal and gave him a copy of the first report that I'd written.  
A: I agree with everyone else -- you should disclose, and I see no problem with this. Let me raise a subtler issue:
A few years ago, I had the experience of being repeatedly sent a paper where the result was correct but, in my opinion, not close to significant enough to appear in the journals where the authors were sending it. I sent a report to this effect twice but, when I was asked to referee at a third journal, I declined on the grounds that the authors deserved a second opinion. If the paper was actually wrong, I would have kept saying so but, in a subjective case like this, I thought it would be wrong to be the referee who killed it single-handed.
A: On a couple of occasions I have been sent the same paper more than once to referee by different editors on behalf of different journals.  In one occasion I even got the paper a third time.
Since I don't think it's good use of my time, not to mention that it goes against the spirit of the peer review process, to rewrite the referee report so that it may pass for report by a different referee, whenever I get a paper a second time, I disclose it immediately to the editor while sending them the previous referee report.  Prior to this, of course, I check that the new version of the paper has not changed: this is some times not as easy to do as one would expect, since some authors try to disguise this by changing fonts, formats,... 
A: I have done this as a reviewer, and have had it done to me as an author.  I have no problem with it.  I do think you should disclose to the editor that you've reviewed the paper before.  (This can create the awkward situation of having to say "I reviewed this for journal A, and didn't think the theorem was interesting enough, but it fits just fine in your journal." But I found the editor in question to be not at all offended.)
A: I don't see any problem with this (especially since the author would suspect it anyway).
