I'm still struggeling to find the right way to lock the phone. The ideal solution would be to:
1) Have the phone unlocked when I switch it on with the Power button (so that I can immediately use it after deliberately turning it on)
2) Have the phone automatically locked when it wakes up due to a phone call, SMS or warning, etc. (so that I don't press anything by accident when it is in my pocket).
This seems to be the only really logical way to use device lock. Obviously, PocketShield can not do that, neither can S2Us or any other locking app I've tried...