Strange kmail 3.1.3 bug

I just ran into an old kmail bug in the latest (3.1.3) version of kmail
running on Openbsd 3.4:

I clicked on the outbox and found a collection of my unsent messages there.
But the first message has subject "no subject" and sender "unknown".
each attempt to delete this message results in the *following*
message being deleted, leaving the "unknown" message untouched.

In addition, attempting to select any message results in the selected
message header beingre instantly placed by the "unknown" message header.

When I shut down and restarted kmail, I got the message that
there were messages in the outbox not created by kmail. At that
time all but one of the messages in the outbox had disappeared.

I don't know whether this is a bug or a virus.

Has anyone else seen this behavior in kmail