Research in Motion is blaming a worldwide BlackBerry service disruption on a network failure in Europe, which has led to a back-log of messages that have gummed up the functionality of the ubiquitous phone.

After days of service problems for BlackBerry users in Europe, the Middle East and Africa, the issue spread to customers in the Americas on Wednesday, including an unspecified number of Canadians.

In a conference call with reporters Wednesday, RIM's chief technology officer, David Yach, blamed the problem on a failure of a back-up system in the company's infrastructure in Europe.

According to Yach, the network experienced a core switch failure, and the back-up system, known as a failover, did not function as expected.

Yach said that with trying to control the situation in Europe, problems have spread around the world.

"We've had to throttle traffic to stabilize service while we process this substantial backlog of messages in a controlled manner," Yach said. "This is why we're seeing ongoing issues, and why we're seeing impact to other regions around the world."

Yach said he believes the company has identified the cause of the glitch in the failover system, but a thorough investigation cannot be completed until service is completely restored.

"We have global teams working around the clock on this, and we are focused on containing the issue and minimizing the impact to our customers," he said.

Yach said users will receive all messages that might be caught up in the backlog.

He also said there is "no evidence" to suggest the problem was caused by hackers or some other security breach.

BlackBerry users overseas began complaining of problems on Monday, and by Wednesday Canadian users reported having problems accessing their email, text and Internet browsing services.

It was not immediately clear how many Canadian users were affected, and the company did not give exact figures when updating reporters about the situation on Wednesday afternoon.

In the wake of the service problems, Canadian users were taking to Twitter to vent their frustrations, get information or provide some perspective on the unexpected service outage.

Manitoba-based social media strategist Ron Cantiveros tweeted that he was "sippin' on my coffee, waiting for the little red light on my #Blackberry to start flashing again."

Donald Blair of Toronto tweeted that he expected his co-workers to "bombard" him with the "folklore" of how the iPhone is better than the BlackBerry, while the service problems persisted.

Even the Prime Minister's Office was affected as Prime Minister Stephen Harper's spokesperson, Andrew MacDougall, tweeted: "Am being impacted by RIM/Berry service outage -- please call if you need to reach me."

New iPhone release imminent

The timing of the outage could hardly come at a worse time for RIM. It has been steadily losing market share to Google's Android smartphones and to Apple's iPhone.

"It's a huge embarrassment for a company that has built its reputation on notion of service and reliability and when all else fails your BlackBerry will still work," Michael Gartenberg, director of research at U.S.-based Gartner Inc, told The Canadian Press.

"It's coming at a time when RIM is facing increasing competition from companies like Google and Apple and Microsoft, all launching new products."

Apple's latest iPhone, the 4S, will be available to the public on Friday and has taken more than one million preorders, according to the company.

The new iPhone comes with iMessage, a direct competitor to RIM's highly-praised BlackBerry Messenger. Some older iPhones can also download the application as part of Apple's new operating system.

Maggie Reardon, of CNET News.com, said the ongoing service disruption has only added to the uncertainty about RIM's future.

"In five years, I don't know what we're going to see, or 10 years," Reardon told CTV News. "I hope that there's still a RIM in the market, but we don't see Palm anymore."

The @BlackBerryHelp feed on Twitter advised RIM customers on Tuesday that the company was in the midst of resolving the issue that has been causing problems for users.

"We're aware many of you are experiencing service delays. Restoring full service is our number 1 priority," the company said. A RIM spokesperson vowed to keep customers updated on Twitter and online until service is restored.

During the conference call, RIM's representatives declined to discuss whether the company may compensate users for the disruption. Late Wednesday, media reports said that the government of Colombia has approached RIM to reimburse customers.

RIM has 70 million BlackBerry subscribers around the globe.