Logs are there really... I have looked for some other pattern, but here they are:
2014-01-10 16:40:34,818 INFO [InventoryManager.availability-1] (rhq.core.pc.inventory.AvailabilityExecutor)- Scan Starting: Fri Jan 10 16:40:34 CET 2014
2014-01-10 16:40:34,883 ERROR [ResourceContainer.invoker.daemon-7] (org.rhq.plugins.netservices.HTTPNetServiceComponent)- javax.net.ssl.SSLPeerUnverifiedException: peer not authenticated
2014-01-10 16:40:34,883 INFO [InventoryManager.availability-1] (rhq.core.pc.inventory.AvailabilityExecutor)- Scan Ended : Fri Jan 10 16:40:34 CET 2014 : Scan [startTime=1389368434818, endTime=1389368434883, runtime=65, isFull=true, isForced=false, numResources=1, numGetAvailabilityCalls=1, numScheduledRandomly=0, numPushedByInterval=1, numAvailabilityChanges=0, numDeferToParent=0]
...
It's a Debian system with Oracle Java 6. The server certs are not self signed, but the CA is not a very well known one.