Despite the uncertainty of the service being clipped on what many Saudis called "a scary Friday" and of reports of temporary interruptions, BlackBerry users were able to access the Messenger service on Friday evening, hours after the Kingdom had threatened to cut it off over concern it might be used to harm national security.

Owners of BlackBerries in Saudi Arabia waited with bated breath for their Messenger service to be switched off on a day of uncertainty. Most of the temporary interruptions were faced by STC users, while Mobily subscribers faced no such issues.

A source with direct knowledge of the negotiations said talks between maker Research In Motion (RIM) and the Saudi telecom regulator Communications and Information Technology Commission (CITC) had made progress.

"We are testing technical solutions with RIM ... Servers to be more exact," the source told Reuters, speaking on condition of anonymity. RIM officials in Canada have not returned calls seeking comment on the talks.

The source said the two options to resolve the row were servers in Saudi Arabia or a patch that would allow the government access to data in cases affecting national security.

CITC did not say whether it had begun enforcing the ban.

India, Saudi Arabia, the UAE, Lebanon and Algeria have all voiced similar concerns that center on access to communications sent through the device. Together, those markets account for about 5 percent of the Canadian firm's global customers.

The US and Canadian governments have expressed concern about implications from banning such services.

RIM's Vice-President Frenny Bawa, who arrived in Riyadh on Thursday, announced her complete readiness to provide the Kingdom with a copy of the data to the competent official authorities. Bawa also said that she had come to present solutions.

On Thursday, according to a source, RIM "showed a degree of flexibility that has not been there over the past three months. Progress is being made. We started debating the technicalities of new set-ups".

RIM has stipulated that any Saudi agreement must apply to the Kingdom's three mobile phone operators: Saudi Telecom, Mobily and Zain Saudi Arabia.

"RIM will not engage in one-to-one talks with the operators about any solution it will adopt. They will have to take it, all of them," the source said.

Some BlackBerry owners in the Kingdom, like Ahmed Zahrani, decided to drive to Bahrain and buy a Bahraini SIM card in order to access to their BlackBerry service. "My BlackBerry messenger contact list includes of people inside and outside the Kingdom and I want to stay in touch with my friends," Zahrani said.

Neighboring UAE has 500,000 BlackBerry users and plans a more sweeping ban from Oct. 11 targeting not only Messenger but also e-mail and Web browsing on the device.

Sources have told Reuters that the UAE government has also suggested RIM install a server handling BlackBerry traffic in the country.

The UAE could access the data it requires either through a local server or an encryption master key used in BlackBerry technology, said Shardul Shrimani, Middle East and North Africa analyst at IHS Global Insight.