After the upgrade to 1.5.6 I checked the Email Bounce Log. I found two entries. Somehow they don't look like the classic bounced - I mean, it looks like someone have send (or tried to do) Spam. There is an attachment, too. As I am a layman to this, I don't know how to handle it. Would it help to understand, if I post the content here or as an (.txt) attachment?