There is no compatibility / conversion possibility betnween 8.7 (and earlier) and the new alert system in 8.8 - they're COMPLETLEY different (apples and jet-engines).
So you would need to re-do your alerts in the new alert system. I'm more than a little surprised that it's "still working" (that seems more of an artifact than anything), so you might potentially want to get in touch with LD-support and have them have a look at your DB...
- Paul Hoffmann
LANDesk EMEA Teechnical Lead.