If you have an Intel-based Mac computer and you’re using Mac OS X v10.4 Tiger or Mac OS X v10.5 Leopard, you can use plug-ins designed for PowerPC-based Macs. To do so, you must first install Rosetta.
Important:Using Safari with Rosetta causes Safari to load webpages more slowly.
Quit Safari if it’s open.
Double-click to open your computer’s hard disk.
Open the Applications folder.
Find Safari in the list of applications, and select it. Choose File > Get Info to open the Safari Info window.
In the General pane, select “Open using Rosetta.”
Close the Safari Info window.
Reopen Safari.