The Waterloo, Ont.-based company Research in Motion appears to have restored service to its popular BlackBerry smart phones Wednesday morning, blaming its second outage in a week on problems with the company's BlackBerry Messenger service.

An unknown number of users across North and South America were affected by the outage, which began on Tuesday. RIM confirmed that the service outage delayed delivery of emails, but said it did not affect phone calls or text messaging.

Some users also lost access to the Internet, BNN's Pat Bolland told CTV News Channel.

The service disruptions appeared to be more or less resolved by Wednesday morning. By then, the company was reviewing the cause of the outage, a spokesperson for RIM told The Canadian Press by email.

"Based on preliminary analysis, it currently appears that the issue stemmed from a flaw in two recently released versions of BlackBerry Messenger (versions 5.0.0.55 and 5.0.0.56) that caused an unanticipated database issue within the BlackBerry infrastructure," the spokesperson wrote. "RIM has taken corrective action to restore service."

The company released a new version of BlackBerry Messenger to help resolve the problem, and encouraged users who upgraded the messenging service since Dec. 14 to adopt the latest version.

The upgrade was released through the company's BlackBerry App World online shop. Instructions regarding the update were posted on www.blackberry.com.

"The thing that's important here is the structure of BlackBerry is said to be impervious to assault... but if it's an internal problem with software, you have these issues," Bolland said.

North American users of the popular line of smart phones experienced another email outage last Thursday. RIM technicians said they located the source of the problem and resolved it. The company didn't say how many users were affected.

Blackberry service was also disrupted in North America for three hours in February of 2008. In that instance, the culprit appeared to be changes made to the wireless system.

Technology expert Marc Saltzman said the two recent service disruptions wouldn't likely lead BlackBerry users, many of whom use the device for work, to opt for a competing device.

"We rely so heavily upon these smart phones that any outage, whether it's a full blackout or a delay in email or messaging is a big deal," Saltzman said. "Fortunately it happened during Christmas break."

The latest outage came as the market for smart phones has become increasingly cutthroat.

"It's a big inconvenience at a time when they're competing with Apple, they're competing with Palm, the Android phones that are coming out from Google, and there are all kinds of new networks being introduced on a global basis," Bolland said.

Still, last week RIM announced that its third-quarter earnings stood at $3.92 billion, an increase of 41 per cent over the same period last year.

The company reported that most of its earnings came from sales of BlackBerry devices, rather than from providing networking services or software.

With files from The Canadian Press and The Associated Press