OH2 / Homematic CCU2 offline

Hi all,

i had a setup using lxccu and OH1 running stable for some month, but then the android app stopped working. That motivated me to migrate to CCU2 and OH2. I set up OH2 (2.0.0 b4) on ubuntu. I moved the homegear devices to CCU2, adapted the things and items file and finally (I thought …) got a more or less working sitemap - ugly, icons missing, but I could set my rollershutters at least via OH web interface (classic UI),

Then i copied the old rules file, restarted OH2 and could never connect to CCU2 since that.
-> while starting OH2, in openhab.log I find
… - Initializing handler for thing ‘homematic:bridge:ccu2’ takes more than 5000ms.
-> in events.log:
… - ‘homematic:bridge:ccu2’ changed from INITIALIZING to OFFLINE (COMMUNICATION_ERROR)

-in the CCU2 /var/log/messages i find:
homematic-ccu2 user.err rfd: XmlRpcClient error calling newDevices({“RF-ccu2”,{[ADDRESS:“BidCoS-RF”,CHILDREN:{“BidCoS-RF:0”,“BidCoS-RF:1”,“BidCoS-RF:2”,“BidCoS-RF:3”,“BidCoS-RF:4”,“BidCoS-RF:5”,“BidCoS-RF:6”,“BidCoS-RF:7”,“BidCoS-RF:8”,“BidCoS-RF:9”,"BidCoS-R
Oct 25 00:37:19 homematic-ccu2 user.err rfd: XmlRpc transport error

Restarting OH2, CCU2, removing rules file, … nothing helps.

Any idea on this?