Missed several days ago, buried amongst apparently official Indonesian testing information, was news that the Lumia 610 smartphone has been approved. We’ll get to the documentation in a moment, but the kicker here is that the 610, a phone that has not been acknowledged by Nokia as being real, is rumored to run Windows Phone Tango.

Tango, a forthcoming alternate version of Windows Phone, is designed to run on low-priced handsets and sports reduced hardware specifications (compared to the ‘normal’ versions of the mobile operating system). Yesterday we brought you leaked news of the corners that Tango would cut to manage lower power phones:

Here are the critical bits: In Tango, the minimum RAM requirement is only 256 megabytes; cameras a low as 3 megapixels will be supported; podcasts will not be manageable on-device; photo upload to SkyDrive will not be turned on automatically; not all apps will run (we assume that apps that require more processing juice is what is meant here); and 3rd party Live Tiles, well, won’t always be live.

That Tango is such a different build of Windows Phone, and that it has the potential to greatly expand the total install base of the mobile line by selling inexpensive handsets in less affluent markets, make it critical to Microsoft’s smartphone aspirations. Indonesia, with a population of over 200 million, but a per capita GDP of roughly $3,500 is a market that phones such as the Lumia 610, provided that it does run Tango, could target.

We’ll hear more as it leaks, but I would gamble that at the Mobile World Congress Nokia will have a fresh packet of information for us. Just for fun, here’s the entry:

2012 02 16 08h52 58 520x18 Nokias Lumia 610 cranks Tango hype with possible Indonesian certification