Hi, I noticed last night that my battery lasted only half as long as usual. So I checked some previous rcs which were all OK. Bisecting led to "0cc2b4e5a020fc7f4d1795741c116c983e9467d7". And reverting that from rc7 restores battery life to its usual state.
(Now, can anyone tell me how to remove the revert I did :) Mike.

