1) It might be your local setup; that perl script is enlisting the aid of sendmail, which is sounding uncooperative. Sorry, this is just conjecture based on the error message.
2) Unfortunately there is a several hour delay before new messages reach the archive; I'm working to increase responsiveness. 3) Not sure off the top of my head what to suggest. 4) Only a few people have imported archives so you may be in something of uncharted territory. It has worked so far, as far as I know. Jeff
