A PlusNet subscriber was surprised this morning to be invited to join Phorm's latest "WebWise" targeted advertising trial, despite assurances that only BT's own customers would be asked for permission to intercept their web browsing.

A PlusNet spokesman said the incident was a one-off, caused by a configuration error.

BT Retail is currently running its third trial of Phorm's technology on thousands of broadband lines. Unlike in the experiments of 2006 and 2007, BT Retail customers are being asked if they want their web browsing to be profiled for advertisers.

Plusnet sent this statement:

Plusnet customers using RIN should not normally see the BT Webwise invitation screen or be able to join the BT Webwise trial. This case is believed to have been due to a configuration error which we acted on as soon as we were made aware of it.

BT and Plusnet have confirmed that no further Plusnet customers should be presented with the BT Webwise screen, and Plusnet customers' web traffic will not form any part of BT Webwise trial.

The firm reaffirmed its position that it does not use Phorm's system on its network, has not trialled it and has no plans to at the moment.

The incident appears to be isolated, but it once again highlights concerns about BT and Phorm's claims for the security of their interception technology, and their ability to operate it to specification. ®

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