I started getting this error as well on 2 of my 3 cisco 7970 phones. Since it was working on one, I knew that something must have changed on the other two but I didn't know where to look. I logged into the terminal and ran
tail -f /var/log/pluto/DCERouter.log
as I tried to get the orbiter to connect. This gave me the cisco orbitor device number that was trying to log in but not much more.
I then went to Wizard \ Devices \Orbiters in the web admin and found the device number (which is listed next to the description field). Then clicked on advanced and near the bottom of the page found
Remote Phone IP
For some reason I do not understand, it was off by one digit: 192.168.80.14 instead of 192.168.80.13
I corrected this field. Saved the page and then did a Wizard \Restart \Quick Reload Router from inside the web admin.
Exiting the orbiter on the phone and then reinitializing it under the Services Menu while the DCERouter.log was running, I no longer got the invalid ip message (who would of thought that it actually was telling you the truth) and saw from the log that the orbiter was actually loading.
My suspicion is that this ip gets coded into that field the first time the phone is loaded and when you change your subnet or for some other reason restart the system after a catastrophe, the DHCP server gives the device a new ip but the old ip is still in that field. Just guessing.
Hope this helps someone who has run into a dead end with this problem.