Strange behaviour with health care parition

I use the health care function for some weeks and since three days I noticed a strange behaviour:

- The Alarm partition is activated via scheduler from 6 in the morning till 11pm.

- I use another rule to send an email if there is no movement for more than four hours.

- Movement is monitored by a motion sensor and two door contacts.

Everything went fine and I got no email for there was more than enough movement. (I watch the data of the Motion sensor quite often because im fascinated by the zipabox)

But when I looked up the data of the healt care partiton i found for the last two days some alarms, even though there was more than enought movement. So for example on the 5th of June I got an alarm at 13:30 and then every four hours. But all the time there was a lot of movement being detected! And despite all the movement the alarm came every four hours from then on.

To make it even more complicated: The alarm was triggered (as can be seen in the alarm history) but there was no email launched. During "real" alarms in the past I always got the email.

Any ideas or did someone had the same Problem? I could easiliy create my own surveilance by using a rule similar to a movement-detector with "join" but I like the idea of health care better and would be glad to be sure it works. Perhaps it is just an internal bug? For me the System seems to work flawlessly, but the data of the alarm partition seems to be wrong.

Klaus