Motile's mail servers are recovering after a major spam attack on one of our clients. Over three thousand virus-infected messages were sent to non-existent addresses at one customer site over a six hour period starting about lunchtime yesterday. The mail appeared to come from a wide range of addresses across the Internet, making them quite hard to filter out.

The flood of mail swamped our virus scanner and spam filters. At one stage it was taking a mail message up to three hours to transit the mail scanner. At no time was any mail lost, with mail queueing not only on our servers, but also on Telstra's servers, under our backup arrangement with them.

The picture improved somewhat over night, but there were still over 1500 mail items queued early this morning.

After a council of war early this morning, we did an emergency upgrade to the mail scanner to speed it up. That was completed at around 11:30am.

At the time of writing (around 11:45am) the queue was down to around 1300 items and is dropping as we watch. We will continue to monitor the situation closely as the day progresses.

We have a plan to comprehensively upgrade and reorganise our mail servers over the course of September to increase our mail handling capabilities by an order of magnitude and to improve reliability as well. These changes should also prevent this problem occurring again.

Mail transit times should return to normal over the course of today.