Build #469, unsolved problem with execution of rules

Hi,

I have a problem with the excution on rules, which is not solved even with build #469.
The problem exists more or less since middle of august, when I switched from beta3 to nightly builds.

The problem is that rules are not executed which are triggered via “Item received command”.
It therefor makes no difference whether the command is send via sitemap (switch) or via another rule i.e. sendCommand(LightsOn_Event, ON).

The funny thing is, that if I delete /var/lib/openhab/mapdb/* and start openhab again, then command triggers work for approx 36 hours.
Afterwards it stops working. In this state, also rebooting does not help, only deleting the db and rediscover all things.

Timer triggers are working absolutly fine, those rules execute as they should.

The log is clean, no strange exceptions or log entrys.

An example of a rule that stops working after some time:

ITEM:

Number ShutterProg <rollershutter>

SITEMAP:

Frame label="Rollladen" {
                Switch item=ShutterProg label="Rolladen" mappings=[1="Auf", 9="Zu"]
        }

TRIGGERED RULE:

rule "RollershutterProg"
       when
                Item ShutterProg received command
        then
                logInfo("shutters", "Item ShutterProg received command")

         .....
         end

In my eyes there is a good chance that this is a very rare problem just for me.
But I have no clue what is the reason for it.

OH is running on a raspi2. The only thing I have changed (together with newly setting up the system and using the nighly builds) before getting this problem is, that I moved the system from a sdcard to an usb ssd.

Again, there are no indicators for problems in the system log.

Any ideas on what to do or try?

Peter