Because it's inadequate.
Pages and Keynote do not provide equivalent functionality even to OpenOffice. That's not the target market.
If you're on OS X, you might as well just get Office 2004; it's somewhat nicer than the Windows version. Filemaker and Access are more-or-less equivalent, with Filemaker having something of a lower suck-quotient.
I thought that an example taken from a Samba list would imply a discussion about functionality on free platforms.
Peter
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