severe load on imap sever by kmail

[Johnny Geling]

I have different email client connecting the same imap server (debian 
woody). I run courier imap from the woody release.

Only with kmail the server is for a longtime (several minutes) working 
on something. It load is arround 80%. It looks like kmail freezes my 
imap server on the connection.

I run debian sid (so kmail 1.6.2
I don't have this with other email clients. (mozilla thunderbird, 
mozilla, sylpheed claws)

Is this a bug from kmail or from the courier imapd?
Johnny