If it ain't broke why fix it?
Why would you want to up date everything works now. higer versions will give more trouble and you can fake it. simply by text edit in you software version. this will allow you to install software that needs a higer version seposedly..

the ancer is yes you nead a higer version but beleave me when i say 10.5.7 is a real dog no one neads that update even breaks intel vanilla installes and even some real mac installations. if you want to fix the appleRTC you nead dsdt patching and only chamelion version 1.11+12 with dsdt overide/ 2.0/2.1 or efi studio v9with dsdt overide/ 10 . you do know you dont have to fix it these days.