In my experience, none of the alarm messages from the hub are configurable. The lack of the hub name (or "tunnel description" from the hub config) in the alarm messages has also caused us some grief in the past. Recently I wrote a custom probe to find out from the hub which tunnels are down and generate more useful alarm messages by reading the hub.cfg file to get the tunnel descriptions. (We used to use net_connect to make sure remote hubs were still listening on the tunnel port, but that did not always alert us when some other kind of tunnel problem would occur.) I think this is working much better for us than the default alarms from the hub itself.
I can go into more detail about how our probe does this if you are interested in doing the same.
Regards,
Keith