Thanks for the quick response -- it appears I have fixed the problem simply by going to blackberry.com and downloading a comprehensive systems update. In so doing I also got a video camera, voice note recorder and some other stuff I'd been missing, as well as an OS upgrade.
Oddly enough, however, a few minutes later my Curve "froze" and I had to pop the battery to get it to recycle -- something I'd never had to do previously in approx. one year of ownership.
Anyway, I fixed the problem, although there may have been a more efficient way to do that; and hopefully I didn't create a new problem. I was just coming back to the forum to post my "solution" when I saw your reply.