I have a dozen or so PKI certificates installed on my computer that I use for testing a web app. They represent the "users" Andy Tester, Billy Tester, Cindy Tester, &c. Fairly frequently, I need to test parts of the app that need multiple users to comment on something, or that behave differently depending on the viewer. In these situations, it'd be nice to be able to change certificates reliably, and if possible quickly.
How can I change which PKI certificate I'm using? Right now, I find that exiting Firefox 3.6/4 completely is necessary but not always sufficient for allowing me to choose a new cert. (In IE7/8, on the other hand, exiting does seem to be sufficient.) If there are multiple methods, fewer steps/easier steps would be preferred. A few websites I've seen recommend just deleting the certs and re-adding them, but that seems so awkward it can't possibly be right.