We continue to cover an issue where the Panther Finder does not accurately update folder sizes when subfolders are modified. This bug occurs whether viewing the folder size in a Finder window (with "Calculate all sizes" enabled for that folder view) or viewing the Info window for that folder (via the Finder's Get Info command).
James Sentman suggests that simply changing the name of the folder in question will sometimes cause a refresh with accurately updated size information:
"I have definitely seen this problem as well. In my case it's a strangely transient thing, works fine for a while and then gets hung up for a while. The easiest way that I've found to jump start it is to just change the name of the folder. When I rename an affected folder the finder immediately seems to realize it's changed and updates the size. This is on a Titanium G4 800 running Panther.
Meanwhile, a new shareware offering purports to force the Finder to update size/content information. The just-released utility, Nudge 1.0, prompts the user to select any Finder item(s) and then asks the Finder to update its display. Under Mac OS X 10.3 (Panther) and up, you can control-click on the empty space in any Finder window and have the contextual menu act on the containing folder.