You have, perhaps, heard about the failure of the T-Mobile USA Sidekick smartphone– known for its remote data storage and the fact that (gad!) Paris Hilton is a devotee – and how Microsoft’s $500 million 2008 Danger acquisition, which invented the thing, managed to permanently lose what looked for a while there like everybody’s data because Danger didn’t back anything up before it or Hitachi screwed up a SAN upgrade or maybe it was a server failure; there are various excuses floating around.

Well, long about four in the morning New York time on Thursday Microsoft – after nobody saying anything since Tuesday, when things still looked pretty bleak – informed Sidekick users that it had managed to recover “most, if not all, customer data for those Sidekick customers whose data was affected by the recent outage. We plan to begin restoring users’ personal data as soon as possible, starting with personal contacts, after we have validated the data and our restoration plan. We will then continue to work around the clock to restore data to all affected users, including calendar, notes, tasks, photographs and high scores, as quickly as possible.”

The notice – over the signature of Roz Ho, corporate vice-president of premium mobile experiences at Microsoft, the person responsible for (ahem) integrating the well-named Danger – also said, “We now believe that data loss affected a minority of Sidekick users.”

She went on to say that “We have determined that the outage was caused by a system failure that created data loss in the core database and the backup. We rebuilt the system component by component, recovering data along the way. This careful process has taken a significant amount of time, but was necessary to preserve the integrity of the data.”

And she said – in between apologies – that “we are taking immediate steps to help ensure this does not happen again. Specifically, we have made changes to improve the overall stability of the Sidekick Service and initiated a more resilient backup process to ensure that the integrity of our database backups is maintained.”

So Microsoft is sticking with the story that a hardware failure took out both the primary and backup copies of the database containing Sidekick user data. Of course it’s unclear how that could happen or why there wasn’t a true backup.

The situation – especially when T-Mobile was telling users it looked like all was lost – cast another long shadow over clouds everywhere and has certainly done nothing to enhance Microsoft’s reputation, T-Mobile’s either or Danger’s for that matter. Google and Apple may count it a win.

Microsoft’s Azure cloud, a different architecture than Danger’s, is due to be unveiled next month at the company’s Professional Developer Conference and Microsoft is going to have another trust issue to deal with.

So it’s distancing itself from Danger and telling inquiring press that “The Danger Service platform, which experienced the outage, is a standalone service operating on non-Microsoft technologies, and is not related to Microsoft’s cloud services platform or Windows Live, underscoring that “Other and future Microsoft mobile products and services are entirely based on Microsoft technologies and Microsoft’s cloud service platform and software.”

It’s also saying that native Microsoft services like Windows Live, Hotmail and Azure keep multiple copies of user data on multiple devices in case physical nodes crash.

Obviously not true of Danger and to make matters worse there’s been talk Microsoft cut support to cut costs after it acquired Danger. By Tuesday there was chatter in the blogosphere of time bomb-based sabotage – caused by hostility over Microsoft’s so-called Pink Project – exasperated by Microsoft’s lack of knowledge of the Danger system or caused a botched brain transplant of Danger’s Solaris/Linux-based Oracle Real Application Cluster to Microsoft architecture. True or not people will believe it. (See http://www.roughlydrafted.com/2009/10/12/microsofts-sidekickpink-problem....)

T-Mobile, the fourth-largest US mobile service and a unit of Deutsche Telekom, has stopped selling the widgets. According to its site Sidekicks are temporarily out of stock.

It’s not clear how many people have been affected; Sidekick is believed to have 800,000-one million users.

T-Mobile has offered users a $20 refund or, for those gravely afflicted, a $100 customer appreciation card to be used toward T-Mobile products and services, or their phone bill by way of compensation. “This will be in addition to the free month of data service that already went to Sidekick data customers,” it said.

Cold comfort that.

Sidekicks function like dumb terminals or thin clients constantly synching with the servers where all the e-mail, web pages, SMS messages, address books, calendars and personal photos actually are. The data’s only on the phone when it’s on and then only fleetingly.

Meanwhile, Sidekick lawsuits are expected; the Wall Street Journal says one has already been filed seeking monetary damages for failing to protect the data and false advertising.