OMG!
The 10.3.9 Update delivers overall improved compatibility and reliability for Mac OS X v10.3 "Panther" and is recommended for all users.Improvements include:
? file sharing and directory services reliability for mixed Mac and PC networks
? Mail, Safari and Stickies application reliability
? compatibility for third party applications and devices
? previous standalone security updatesFor detailed information on this Update, please visit this website: http://www.info.apple.com/kbnum/n300966
For detailed information on Security Updates, please visit this website: http://www.info.apple.com/kbnum/n61798
Oh! I wanted to say... Make sure you ALWAYS run fix disk permissions after installing updates. Otherwise you will encounter nasty little gremlins in your machine. Eventually. With OS X it's good to keep it clean.