Uunet's one million Pipex Dial customers will have to wait until at least the middle of the week for email services to be restored after last week's crippling spam attack.

The ISP is currently manually removing the unsolicited batch of two million messages, but despite staff working all weekend, it said on Monday that it expected its email server to operate slowly for another 48 to 72 hours.

As reported last week, Uunet was floored by a flood of unsolicited commercial email early on Thursday. It said the spam, which originated in Canada, had crippled its eight email servers.

In a statement issued today, Uunet said: "Although most of the [spam] mails have now been deleted, the quantity of genuine mail stored is so great, the system, which serves around one million users, is continuing to pass mail only slowly. We currently believe that no mail has been lost.

"Uunet is taking all reasonable steps to ensure there is no repetition of the UCE attack of last week and is pursuing the perpetrator... Uuunet apologises for any inconvenience caused."

Uunet spokesman Richard Woods told vnunet.com: "We have identified where the message came from, and we are talking to the North American ISP that was used to try and identify who it came from.

"We will then take whatever action makes sense. We're minded to take whatever legal action we can, although we don't think it was a deliberate attempt to bring our servers down."

Woods said the firm had not ruled out compensating customers for the outage outrage, but pointed out that contract terms and conditions did not include a time limit on the delivering of email.

"We're aware people suffered and we're taking it under review," he said.

Woods added that email problems experienced by some users last Wednesday were unrelated to the spam attack, but were caused by an unrelated server failure and lost connectivity in the Docklands area of London. He also dismissed suggestions made in newsgroups that trials of new email servers may have made the problem worse.

"We've had problems with our mail server system for the past three or four months, as it is serving its limit of a million customers," he said.

"We begin the process of bringing a new system online next month. However, it wasn't being trialled last week. I only wish it had been, as it would have given us that much more capacity," he added.