Thanks to all for your responses. As an FYI, I *think* we've determined that it's not a problem with the WAP settings, but rather is a problem with MDS and the IT Policy. They think that the fact that it was working flawlessly before was just a fluke and that it probably shouldn't have been working at all. IT is working on setting up exceptions for me now, and with any degree of luck, it'll work. I'll let you all know what happens.
Again, many thanks.