Trending Interfaces without IP addresses

Hello,

I have several IDS sensors that I would like to take bandwidth snapshots of the IDS interface. I noticed that the ifstat command to grab the statistics only grabs statistics for the interface with an IP address assigned to it; I have tried modifying it to grab the statistics for the unnumbered interface, but it still does not return any data. The sensors run FreeBSD.

So, does anyone know of a way to get Xymon to gather statistics of an interface that is up with an active link (one-way tap) but does not have an IP address?

Thanks,

Conrad