The calibration problem is a known bug in the calibration app, not in the kernel.
It's mentioned in the kernel package description and is due to additional evdev (joystick,mouse) support.
Just calibrate once with the stock kernel before you install the fully featured kernel.

@psrkn: The warning in dmesg is only expected for kernels other then the ULV kernel.
So far only the ULV kernel has 810MHz but I'm just rebuilding the LV and the normal voltage kernel with it.

@ahmadamaj: performance should be independent of voltage.

@psrkn: you dont need to uninstall the previous kernel. the new one will just overwrite it.

ULV should improve battery life and reduce CPU damage but it may be less stable.

For the new battery module you need to "modprobe bq27x00_battery" first.

current low voltage kernels:
http://talk.maemo.org/showpost.php?p...postcount=2004