Xperia Mini: Overheating fix and CM 9
The Xperia Mini phone has a very common issue, caused by overheating. My phone suffered from this same issue. Browsing the web using Wifi lasted for about 5 minutes, until the overheating issue made the phone unusable.
To fix this issue, the soft buttons must be recalibrated as described in this blog post. I was sceptical about flashing the original software just for calibration and then reflashing CyanogenMod. I assumed, the calibration is done merely in software. As a matter of fact, it is possible to reflash CyanogenMod after the calibration was performed. The calibration will stay intact.
While doing a lot of flashing, I decided to try CM 9. The official CM 9 RC1 release did not work out of the box. There is a kernel issue, that makes the hardware buttons unusable. Additionally the acceleration sensors do not work and the display will stay in landscape mode. Using the FXP128 kernel, eveything works beautifully.
One outstanding issue with the Xperia Mini is the poor touchscreen. Fast movements are not recognized correctly, and may lead to unintended clicks. This is not solved in the latest CM release and may never be fixed.