Sorry, mjl, for not posting more detail
You are a busy person! This is following another thread in which you were very helpful, regarding finding a webcam that would work in the first place... Getting there!
The good news is, in poking around on mythweb hoping to jog my memory to answer your question, I found the problem!
For posterity in case anyone else has the trouble, here's the scoop:
At first, after setting up the Phillips camera as described in this thread, I was able to see the preview image, but not make any calls. So I temporarily disabled my firewall and put the "NatIpAddress " setting to the outside IP that the cable internet provider had assigned. Not a long-term solution, but enough to see that indeed, I could at least receive calls, sending and receiving video.
Now, I wanted to make it so that my dynamic ip would work, so I wanted to change the IP to "Web Server" and lookup my IP from dyndns.org. Seems I only got halfway done. I had set the method to "Web Server", but apparently hadn't yet set the address from the static IP. So I'm guessing that when Frontend was launching... mythphone was trying to log in, and got in a loop where it was trying to "lookup" the address from itself, and crashed.
That's my story and I'm sticking to it.
Anyway, when I saw that preference/ip combo in MythWeb, I changed the preference to "Manual" and launched Frontend, it worked without a hitch.
Yay!
)