zope-2.7.2 has been available in portage for a couple of weeks now.
It has? It must still be masked, then. I emerge sync nightly, and 2.6.4 came up as the most recent available when I emerged the other day. Thanks to everyone who responded! I'm going to try the 2.7.2 emerge first, and see if that sets everything up appropriately. If not, I'll look into the other suggestions. I'm only an emerge end-user myself, and don't know the first thing about writing or hacking ebuilds at this point (nor is this the time for me to delve deeper into that ;), so I'm unlikely to follow that particular suggestion. However, I have a clearer idea of what's going on now. That zope shouldn't be running as root is definitely a good start. Thanks again, Steph