By Lester Kok

THOUSANDS of cellphone users who pay more to be on SingTel's multi-SIM service have been hit by two major disruptions in the span of two weeks.

The recent disruptions left them uncontactable for hours even though their phones appeared to be working.

The multi-SIM service, which allows one cellphone line to have up to four SIM cards in different phones, first crashed on Oct 22 at around 5pm and it took around six hours for the service to be restored.

Users could not receive any calls or SMS messages during this time. Some could still call or send out messages, but a handful were unable to do either.

For those who could make calls, a 'dummy' eight-digit phone number would appear on the called parties' phones, so they did not recognise who was calling them.

Just two weeks later, on Nov 6, the same problem happened again. This time, the crash lasted for eight hours, from 1pm to 9pm.

The Infocomm Development Authority said it is looking into the case, and that there are minimum quality of service standards put in place to ensure telecommunications companies deliver good service coverage. Any breach in standards can result in a fine of up to $5,000.

The multi-SIM service was first launched in Singapore in December 2005 by M1, with the other two telecoms companies offering the same service shortly after.

As this is a value-added service, the telecoms companies said they are unable to reveal the number of subscribers.

The multi-SIM service is commonly used by people working in sensitive jobs which require them to carry non-camera phones to work.

To subscribe to the multi-SIM service, a customer has to buy a special SIM card which costs between $10.70 and $37.45, depending on the provider.

The one-time activation fee is $10.70 at all telecoms companies, and the monthly subscription ranges from $5.35 to $11.77, depending on the number of cards.

SingTel's service allows up to four SIM cards, while M1 allows three cards and StarHub two cards.

The two lengthy disruptions have annoyed SingTel's multi-SIM users.

Manager Frederic Hoo, 34, missed an unscheduled business meeting when his firm could not contact him on Nov 6. 'I wasn't available to make the decision required and someone else eventually made the decision because they couldn't get me,' he said. 'Potentially, the company's revenue could have been compromised.'

Mr Hoo's wife, who is on the same multi-SIM service, was also uncontactable. 'I was taking care of the baby at home, and I couldn't get her on the phone. Luckily, nothing happened to our baby during that time,' he said.

A SingTel spokesman said the first incident last month was due to a software glitch between the multi-SIM system and the mobile gateway, while the second incident was another glitch between the multi-SIM system and the database.

SingTel has been working with its systems vendor and so far things have been okay, its spokesman added.

The disruptions affected only multi-SIM users who were using their secondary SIM card.

SingTel said the disruptions affected less than 0.1 per cent of its customer base, although it did not give specific numbers. SingTel has about 3.1 million subscribers.

For those affected, the company said it would waive the charges for calls made and SMS messages sent during the period.

However, some users said they have had their entire phone bills of up to $500 waived after they called in to complain.

Others, like Mr Gordon Yeo, 30, who complained to the telco, said SingTel offered to give him a waiver but did not tell him the exact amount.

'I do not think there would be any form of compensation if I did not make any complaint that day,' the IT manager said. 'I believe many other users who are on multi-SIM service probably aren't aware of this incident at all.'

Mr Welly Tengara, 30, said: 'I received no compensation as far as I know, not even an apology SMS from them. I hope they can improve on the service, otherwise I would rather change back to a single SIM card.'

lesterk@sph.com.sg

For more The Straits Times stories, click here.