[Observium] ARP Table empty

Hi list,

The "ARP Table" on all ports is empty (f.e. /device/device=95/tab=port/port=13844/view=arp/), I'm wondering why... Shouldn't there be listed all MAC addresses in the MAC address table ("show mac address-table")? Or is this really just the MAC<->IP table? If yes, are MAC addresses tables saved in the Observium database to see which MAC address is on which switchport? Looking at the "ARP Table" from all Ports (f.e. /device/device=95/tab=ports/view=arp/) there are MAC adresses which belongs to an IP address.

All devices are Cisco Switches or Brocade Router.

Cheers, Tobias