If Facebook is the technology world's equivalent of a precocious teenager, Microsoft is its middle-aged uncle who isn't quite cool enough to make it onto the friends list.

That, at least, is the impression they've been creating lately. First, the popular social networking site was slower than many others to plug into the Redmond company's revamped Windows Live service -- despite the fact that Microsoft is one of Facebook's minority owners. Now, Mark Zuckerberg & Co. have left it up to Microsoft to lead the development of Facebook's own Windows Mobile application.

No, in case you're wondering, that isn't how it usually works. In contrast, most developers wait anxiously for Apple just to approve their apps. Sure, Facebook is hugely important for Microsoft to have in its new Windows Mobile store. But what does it say about the company's desperation to compete with the iPhone, and others, that it's resorting to making third-party programs for its own platform?

The arrangement was disclosed without fanfare this week toward the bottom of a Microsoft news release about the initial wave of apps for what the company has named the "Windows Marketplace for Mobile." The release said, as if it were perfectly normal, that "Microsoft has created a new Facebook application" for the store.

"Why did Microsoft create the Facebook application and not Facebook? You tell me," wrote Joe Wilcox of Microsoft Watch after noticing the unusual line. "Perhaps Microsoft developers think they can offer more, or perhaps Facebook doesn't have enough interest."

I asked Microsoft: Why didn't Facebook make its own app?

"We took a collaborative approach with Facebook in bringing this application to market," said Microsoft's Greg Sullivan, in an email response. "While we led development efforts, the two companies worked closely on building, testing, and approving this app so that the experience would be intuitive and feature-rich for Windows phone owners and for Facebook users."

I wondered if this would become a regular thing -- whether Microsoft would routinely devote its own resources to make Windows phone apps for third-party sites.

"Virtually all of our 20,000+ application catalogue has come from our ISV partners, and we don’t expect this to change," Sullivan responded. "We do occasionally take the lead on application development with products like Windows Live for Mobile and this Facebook app. This allows us to share key learnings with our larger development community."

Of course, Windows Live is Microsoft's own offering, so that's not exactly the same thing as an operating-system vendor making an app on its own platform for a third-party site. But maybe if the whole Facebook arrangement is truly a case study -- a learning opportunity for others -- Microsoft doesn't come off as nearly so lame.

Even so, just to be safe, Facebook's Zuckerberg might want to throw some virtual flowers at Bill Gates to smooth things over -- assuming, that is, he has accepted the Microsoft chairman's friend invite.