It's hard to debug javascript in IE, but it's even harder to debug without the actual url, or when using minified javascript. You might want to switch to the full non-minified version of jquery temporarily, so that you can find the line where the error occurs and see what's going on.
Also, in firefox you can try using firebug to see if it throws any errors. Even though the map is working in firefox, it may be silently recovering from an error that IE can't recover from.