Disappointing sales have led Microsoft to cancel its Kin mobile phone initiative a little more than a month after the company launched the devices, according to sources close to the company.

The decision was announced internally today by Andy Lees, the head of Microsoft's mobile division, bringing a quick conclusion to a high-profile and ultimately futile effort by the company to capture the attention of teenagers and young adults.

Gizmodo and Engadget reported the news a short time ago, and we were able to confirm the details independently.

Without publicly acknowledging the reasons for the decision, Microsoft released a statement saying that it has made the decision to "focus exclusively" on Windows Phone 7, the upcoming revamp of its smartphone operating system, and will not ship the Kin devices in Europe this fall as planned.

"Additionally, we are integrating our KIN team with the Windows Phone 7 team, incorporating valuable ideas and technologies from KIN into future Windows Phone releases," the company said in the statement. "We will continue to work with Verizon in the U.S. to sell current KIN phones."

[Follow-up: One keeper from Microsoft Kin]

Even though Microsoft says the technology will be incorporated into its broader mobile initiatives, on the face of it this looks like a costly lesson for the company. The Kin devices were the result of extensive development under the code name "Project Pink," and based in part on technologies acquired by Microsoft in its $500 million purchase of Danger Inc., the company behind the T-Mobile Sidekick device, two years ago.

Verizon earlier this week cut the prices of the devices to $30 and $50, respectively, in what appears, in hindsight, to have been a prelude to end of the Kin. Not helping matters were the costly monthly service plans, starting at $39.99 for voice, and $29.99 for mobile email and web access.

The phones focused heavily on social-networking features, syncing content from the devices to a web-based portal called the Studio, for easier access.

Although the devices will be joining Microsoft Bob in the company's scrapheap of short-lived products, the few Kins that were sold could at least become collectors items. Microsoft has neither confirmed nor denied reports that only 500 of the Kins were sold since the launch last month.

[Previously: The problem with Microsoft's Kin]