Just to report: I made the update to 10.5.5 using the combo-updater, on the day it came out, having repaired the permissions first, and having 2 complete backups. 10.5.4 and a few earlier updates have been a bit unstable on my Sept-03 aluminium G4 Powerbook. This seems better, but not perfect. I got one kernel panic upon updating / restarting, but no issues since then. regards, Trevor