Just mentioning it here as it might help other people solve issues with this OH2.1 just after upgrade
In OH2 a rule file containing:
if receivedCommand != 3 {
worked.
In OH2.1 it causes an error because of which the rule file is ignored. Changed it to:
if (receivedCommand != 3) {
Now it works again. But had me baffled as I updated a working system that appeared not to work after the upgrade. This turned out to be the reason, it was even in the log but I list that in between all the other stuff 