KMail 1.12.3 - downloads all messages multiple times

Hello all,

I've recently run into a problem with KMail, where once every day or two, 
it'll download all of my past emails from the pop3 server (for hotmail), even 
though they have already been downloaded before.  I have my account set to 
leave messages on the server for 7 days.  Immediately after this happens, 
KMail resumes operating normally again (it's set to check every 30 minutes).  
There's no pattern as to when this happens (it could be on KMail startup, or 
when the email is checked either manually or automatically at one of the 30 
minute intervals).

Is this a known issue?  Would it be a problem with KMail, the Hotmail pop 
servers, or a combination of both?

I checked online and couldn't find anything.  I've been using KMail for nearly 
a year now, and it's only in the past week or so that it has started to happen 
(since I upgraded to Fedora 12 I think).

Any suggestions?

Regards,
Mike