Hi,
If you are talking about the larger left margin on the main content then this is a known problem with the left margin of the float nearest the left windows edge (or the right margin of a float near the right windows edge).
In these cases IE for some reason gets the margins wrong and almost doubles the margin. Subsequent floats and margins are ok.
The solution I use is to give ie a different margin to compensate although you will need to fiddle with it to get it exact.
Code:
* html #contentMain {margin-left:10px}
Only ie will get the above style and even things out.
Hope that helps.
Paul
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