Microsoft has released a pair of updates:
MSN Messenger 4.0.1, a maintenance update that’s mandatory for all users, and
Office v.X for Mac Security Update 10.1.6, which “addresses several stability issues with Microsoft Word, PowerPoint, Excel, Entourage, and Microsoft Visual Basic for Applications for Office v. X.” Both are free upgrades, although the Office v.X update requires that at least one of its applications — Word X, Excel X, PowerPoint X or Entourage X — is installed on your Mac.
MSN Messenger requires Mac OS X v10.2.8 (v10.3.3 recommended), a G3 processor, 128MB RAM, 12MB hard drive space and an Internet connection that’s 28.8Kbps or faster. Office v.X requires Mac OS X v10.1, a G3 processor, 128MB RAM and 36MB hard drive space.