I own a 12" powerbook G4 and a dual 1.25 G4 powermac and after updating to panther I have lost classic support and for the life of me I cant figure out how to reinstall it. I was told to download the most recent version of OS9 which I did but when I tried to install it the computer states that it requires classic support for the install. Another issue that I have ran in to with my powerbook is that when using the 10.3 installer it runs in to major issues because of my aftermarket ram. Any suggestions or knowledge on these issues would be much appreciated.
DeltaMac
Tech
Problems with not-quite-compatible RAM has been bounced araound here many times. Most memory has a money-back warranty. 
Boot up your system, insert your software restore DVD, and click on the choice to install Classic (OS 9)
Refer to THIS ARTICLE for more help.
Boot up your system, insert your software restore DVD, and click on the choice to install Classic (OS 9)
Refer to THIS ARTICLE for more help.