Cable operator NTL Ireland has suspended its offer of residential voice services, claiming that the Tellabs Inc. (Nasdaq: TLAB; Frankfurt: BTLA) units installed in homes to help provide the service were a potential fire hazard.

The operator, which is arranging for the 2,000 customers affected to be transferred to the voice service of Ireland's national carrier, Eircom Ltd. (London: EIR), informed the country's Commission For Communications Regulation that it was concerned for the safety of those customers.

In a statement, the regulator noted that NTL "is concerned that the equipment which they installed in customers' homes may, in certain circumstances, constitute a potential safety hazard through overheating." The regulator also believes NTL could have done more to warn its customers about its concerns.

NTL, which sent letters to the customers telling them to unplug the units immediately, says it has put the safety of its customers first, and began collecting the Cablespan units from people's homes over the weekend.

But Tellabs denies that its products are dangerous. In a statement prepared in response to NTL's claims, the vendor says it is confident that the product is safe "when properly installed."

The vendor says more than 600,000 indoor Cablespan units have been installed since 1998, and that the "two isolated incidents involving potential health and safety issues" reported by NTL were probably, but not definitely, caused by "improper installation of the equipment." Tellabs says it is working with the cable operator to determine "the exact cause of the incidents."

Tellabs says the units deployed by NTL Ireland are its 2303-2N68NW, 2303-2C68NW, and 2303-2C68FG indoor service units, which are used "by various companies around the world." While Tellabs didn't specify those various companies, they include AT&T Broadband, now Comcast Corp. (Nasdaq: CMCSA, CMCSK), in the U.S., and European cable operator United Pan-Europe Communications NV (UPC) (Nasdaq: UPCOY).

This isn't the first time that the Cablespan product family, which includes the cable modem termination unit (CMTU) that channels data traffic to the customer premises units, has been at the center of a Tellabs hoo-ha (see Riverstone and Tellabs in Bustup).

— Ray Le Maistre, International News Editor, Light Reading