My 2009 e90 has the "cornering lights failure" warning come up about once a month and has done so since new. The cornering lights don't come on when the warning is present, and neither do the xenons adapt by refocussing as speed rises and falls. Shutting the ignition and lights off, then back on again doesn't fix it either, but then next day there's no problem. My dealer reset or reflashed the computer which they thought might fix it, but the warning still intermittently returned.
In 2010 I replaced the bulbs in the cornering lights as a mod to get all front end lights at 6000k. Still the problem persisted and does so today in 2013. My dealership doesn't want to know about it as they know the current bulbs are aftermarket, regardless of the fact it also did it with the original bulbs. I don't want to spend much money on it as it's only intermittent, but it is pretty annoying.