Apple Computer has released a free Mac OS 9.0.4 which claims to offer enhanced USB and FireWire support, provide improved networking and power management, plus improve video, graphics, and audio functionality. Mac OS 9.0.4 is a maintenance release; it does not add new features. The update itself is a 12.2 MB download, and it is available either from Apple's servers or from Mac OS 9's Software Update control panel. As of this writing, versions are available for North American English (at the first URL below) plus International English, French, German, Italian, Japanese, Spanish, and Swedish. Additional localized versions should be available soon.
Owners of Power Mac G4s, PowerBook (FireWire) systems, and slot-loading iMacs will also need to download and install Apple DVD Player 2.2 to support their systems' software-based DVD decoding. Owners of blue and white G3 systems, PowerBook G3 Series, and PowerBook (Bronze keyboard) can stick with Apple DVD Player 1.3, since their systems decode DVDs in hardware.
What's New -- You'd think a 12 MB system software update would include a ReadMe file explaining the changes - but in this case, you'd be wrong. Also missing is an uninstall option: once you've upgraded to Mac OS 9.0.4, reverting to a previous version of Mac OS 9 involves re-installing from scratch. As with any system software update, be sure to do a complete backup before installation, just in case.
The limited information Apple has released indicates Mac OS 9.0.4 should address DVD playback problems on recent Macintosh systems, fix a bug preventing slot-loading iMacs from going to sleep with an active PPP connection, and improve compatibility with third-party FireWire cards. Apple has published a developer technical note on Mac OS 9.0.4, although it mashes together information from Mac OS 9.0 as well as the hardware-specific Mac OS 9.0.2 (for some iBooks, Power Mac G4s, and FireWire-equipped PowerBooks) and Mac 9.0.3 (for some slot-loading iMacs), and contains a number of apparently inaccurate statements.
So far, our limited experience with Mac OS 9.0.4 and our interpretation of the information available about the update indicates you can expect the following additional tweaks:
Open Transport 2.6.1 fixes a number of DHCP networking issues, and includes changes to support the AirPort base station as well as the patches hastily rolled out in Open Transport 2.6 to prevent possible abuse as a traffic amplifier in a denial-of-service attack.
Machines should automatically reboot more reliably after a power failure if they've been set to "server mode" in the Energy Saver control panel.
The Battery Monitor control strip should display improved estimates of remaining battery time on PowerBooks that support a second battery.
Fixes a bug in Mac OS 9 so that the PowerPC-native SCSI Manager is installed at system startup, rather than the version of SCSI Manager in ROM. This should improve SCSI performance of older Power Macs (released before, say, mid-1996) running Mac OS 9.
Glacially slow visual effects in HyperCard on Power Mac G4 systems now work correctly (although this problem was corrected in Mac OS 9.0.2).
What's Not Fixed -- Mac OS 9.0.4 does not address the data corruption problem affecting iBook and PowerBook (FireWire) systems using the "preserve memory contents on sleep" option in the Energy Saver control panel; like Apple's Sleep Memory Extension, Mac OS 9.0.4 merely blocks access to the feature. We've also received numerous reports of problems connecting to USB devices under Mac OS 9.0.4, especially HotSyncing with Palm devices. In addition, devices like TV tuner cards from the now-defunct ixMicro which had audio difficulties under previous versions of Mac OS 9 may lose audio capability altogether.
Our Advice -- The benefits of Mac OS 9.0.4 are mainly aimed at newer Apple hardware, so if you have an older Mac (without USB and/or FireWire) the update may not be useful unless you're suffering from one of the few specific problems it fixes. Otherwise, the update is a good idea, but watch out for problems it introduces.