Currently Being ModeratedJun 7, 2013 2:10 PM (in response to ThorTheMongoose)
There is a shorter way to Reinstall in OS X 10.5.8
Stick your Install DVD into the computer.
Open the Disk in a Finder window.
Drag the window large enough to see the "Optional Installs" Folder.
Open this and double click the OptionalInstalls.mpkg
This will launch the Installer and by default will eventually show you a list of App and Printer options that can be Installed.
Make sure iChat is the only ticked Item and click the Install button.
This is likely to be an Install Disk at version OS X 10.5.0 (or plain OS X 10.5)
This means the iChat version is at a lesser version as well.
iChat versions need to "Match" the OS Version.
To do this you need to download and run the COMBO version OS Update
This will then Update iChat to the correct Update point (Version 4.0.8)
Both methods are detailed here
iMac 2.5Ghz 5i 2011 (Mountain Lion 10.8.4)
G4/1GhzDual MDD (Leopard 10.5.8)
MacBookPro 2Gb (Snow Leopard 10.6.8)
Mac OS X (10.6.8),
Couple of iPhones and an iPad
"Limit the Logs to the Bits above Binary Images." No, Seriously