Replacing akmd with an older version works!
Replacing the current akmd version with an older one (I took it from JF 1.42) did the trick for me, too. This should really go into some FAQ.
- Get old version of akmd (for convenience, I put the JF 1.42 one on my server, you can download it from here)
- Unzip akmd.zip and copy the resulting file akmd to the SD card
- Get a root shell (su)
- Mount /system read-write (mount -o remount,rw)
- Copy the downloaded akmd over the present one (cp /sdcard/akmd /system/bin/akmd)
- Adjust akmd's permissions (chmod 755 /system/bin/akmd)
... and your accelerometer should be working again.