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The instructions from MacroMates are working for me, and I am using Safari on Leopard with SafariBlock right now. :)

You have to place the SafariBlock bundle in the /Library/InputManagers folder (not your local user Library) and then run the chown command from Terminal to assign the proper ownerships to the bundle files.

Please see this thread for complete instructions.

Thanks. I tried this too, but still no luck.
 
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