Apple has released Firmware Update 4.19 for Power Mac G4s, G4 Cubes and slot-loading iMacs.

The update improves start-up in Mac OS X, as well as FireWire target-disk mode, network startup, improves gigabit networking on so-equipped systems, and improves system stability. It also supports additional security options that allow Open Firmware to be password protected.

The update for Power Mac G4 will run only on Power Mac G4 models with AGP (Accelerated Graphics Port), running Mac OS 9.1 or later.

The update is also available only to iMacs with slot-loading CD or DVD drives.