"Microsoft on Tuesday issued updates for its venerable Office suite versions 2004 and 2008. Office 2004 gets a security boost with the Mac 11.5.6 update, which corrects a vulnerability that could allow a remote baddie to overwrite your computer's memory. The 2008 version sees the same security fix in its Mac 12.2.3 update, plus a host of other minor upgrades, such as resolving text spacing issues in documents that originated on Windows system."
This also helps with instability in Word, as well as Excel and PowerPoint. Entourage is also upgraded with an improved junk mail filter. The 2004 update requires OS X 10.2.8 or newer and also that the previous update 11.5.5 be installed. For the 2008 update you need OS X 10.4.9 or newer with the previous 12.1.0 update having been installed prior to this one.