I don't think you can (unless you're some kinda hacker or I'm wrong and there actually is a way to do it...). LW just detects the newer version and will keep on bugging you to update your own until you do. Maybe you should try it: who knows, maybe it might work great too...

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iMac G4 OSX 10.3.9
RAM 256MB
LW 4.10.5 Basic
ADSL anything from 3 to 8Mbps/around 1024kbps

"Raise your can of Beer on high
And seal your fate forever
Our best years have passed us by
The Golden Age Of Leather"
-Blue Öyster Cult-