I'll post it directly here:
It's a bit of a confusion in Leopard. Start by downloading Pacifist at
VersionTracker or
MacUpdate. Open Pacifist.
Insert your Leopard DVD into the optical drive. Select Go to Folder from the Finder's Go menu and enter:
/Volumes/Mac OS X Install DVD/System/Installation/Packages/
Click on the Go button. Locate the OSInstall.pkg file and drag it to the Pacifist window. Click on the Resources tab in the Pacifist list window. Open the Scripts folder and locate the hidden_MacOS9 file and click on the Extract to icon in the Pacifist toolbar. I would extract it the the /usr/sbin/ directory. Now Open the Tools folder and locate the SetHidden command. Select it and click on the Extract to icon in the Pacifist toolbar. Extract it also to the /usr/sbin/ directory.
Now you can quit Pacifist. Open the Terminal app in your Utilities folder. At the prompt enter:
cd /usr/sbin
sudo ./SetHidden / hidden_MacOS9
Enter your password which will not be echoed.
If you have the Developer Tools installed you do not need Pacifist. Instead, after copying the OSInstall.pkg file, right-click on it and select "Open with -> Flat Package Editor", then drag the "Scripts" file to the Desktop. Double-click the "Scripts" file, or right-click on it and select "Open with -> Archive Utility (10.5)". A folder named "Scripts 2 2" with be created on the Desktop which contains the items mentioned.
