If you have problem that can't loading wacom tablet driver at startup, do try as following :

1. Just add "TabletDriver.app" to your "Startup Items" (System Preferences > Accounts)
    * the "TabletDriver.app" located in :  /Library/StartupItems/Tablet/TabletDriver.app

2. Done. (restarting or log-out/log-in required to take effect)

After this, you never can meet the problem again. (no problem since 2003)
but, I using wacom driver v4763 with G2 only and so not sure it work on latest versions. good luck !