lol, IE 6? There is no IE 6 for Mac! I assume you mean 5.x?
A quick google leads me to suppose that getElementById is not implemented in IE 5 for Mac.. so either the erroneous task of browser and platform detection is in order, ignore it all together (lots of Mac users are diehard users of browsers like Safari and Mozilla anyway), or take another approach. Microsoft has abandoned its standalone IE browser for all platforms, in Windows its being integrated with their next OS. So a new IE for Mac is never going to happen! Instead they've done a browser in MSN for OS X, which has fantastic support for standards. Personally I wouldn't worry about it too much.
Regards,
Rich
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The Spicy Peanut Project
http://www.spicypeanut.net
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