We have been investigating this and think we have found the problem. We purchased a database cleaner that allows you to delete comments from a set date. It is supposed to delete comments from guestbook, but it appears it is also deleting comments from blogs. The last cleanup was July 3rd and earlier; upon checking old blogs prior to that date, it does appear comments are gone (it still leaves number of comments listed even though they are not there). I have reported this to the company who made this script and in the meantime will not be clearing old comments.
Glad you noted this and reported it as we were not aware of this issue. We apologize for any inconvenience this has caused.
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