Notes/Domino 6 and 7 Forum : Memo form corruption and date change after server crash

I have 2 clustered R6.5 servers with Version 508 clients. The server crashed in the morning (but that's another story !) and after that, one persons (out of 1000) mail file got a bit messed up. Some of the mails have been corrupted in that they have all changed display date to 01/01/1993 (and they all have a create date - in document properties - of yesterdays date) and the form seems to have changed so that the 'from' in the letter head is the mail file owners name but they also contain a 'sent by' name of the actual sender of the mail. Most of the mails are external to internal mail so these mails could not have been sent from the users mail file. Also his 'from' name is incorrectly suffixed with the actual senders email domain. So the mail would say:

My User@yahoo.com, sent by external.user@yahoo.com.

My user would have originally been listed in the 'to' field which is I guess where the corruption has got the letterhead name from. This person is also a laptop user but I'm not sure whether this would make any difference. I hope this makes some sense. I've never seen this before and have no idea why it has happened.. so I'm doubtful if anyone else would have experienced it. But if you have any ideas I'd love to hear them!