Photoshop 6 upgraded to 7 and CS on a G4 to install on new intel-mac

Hi,
I purchased few years ago photoshop 6 and then upgraded it to CS. problem is that I just purchased a brand new macpro and since osx is no more os9 compatible I cannot re install pS6 and do the upgrades.
Is there a way to do this?
I spent a lot of money for the original product and the updates and it seems sad that i just cannot use this program on a new Mac.

any help is welcome

Thanks

Marco

Just load the software and enter the old serial number when asked.

What Buko says. The upgrade is a FULL INSTALLER; if it does not find an older version installed, it will simply ask you for the older serial number.