It seems it must have been a known problem - an associate who'd been experimenting with a prototype of our software using a newer version of AOLServer reported that everything still worked fine.
In any case, he was able to provide a temporary fix for the problem by setting up a crontab entry to run a script file that contains a wget to get a page from our website, and we put some code in that page to call all the required scheduled methods. It's a bit roundabout, but at least it should save us from having to franticly trying to update a production website in the short term.
