Well, color my face red. The explanation is something I simply hadn't thought of but which became obvious when I expanded the headers on the notification message.

I have a duplicate site on a different domain that I use to evaluate modules, etc. Benny had actually registered there. I didn't recognize that the notification email came from there as it is not a public site and the notifications look identical unless the headers are expanded.

Registering on that site does make it clear that it is a spurious registration. Clearly some robot is trolling for places to register.

So, Xoops is in fact behaving normally. It's just me that is not. I apologize for the confusion and for wasting your time. No need to examine the logs.

barryC