No errors, but also no markers, on IE 6

I'd appreciate any help you can give me.

I'm working on a GoogleMaps application at:

http://www.atlasoffiction.com/maps.html?world

It works just fine on Firefox for Mac OS X and Windows, but when I try
to load it on IE 6.0 on my work machine, the markers don't load.

I can see the map; my JavaScript controls work just fine; and I don't
get a JavaScript error. But there aren't any markers on the map.

Does anyone have any ideas?