The last element in the holding division is a clerarance division with margin-top: 20px; height:0px; font-size:10px.
The green floated division should exactly fill the content height of the red holding division.
With MSIE7 this fails and there is a gap equal to the merged values of the bottom margin of the heading (The last inflow element).and the top margin of the clearance division.
With MSIE6 the gap is equal to the same bottom margin plus the font size in the clearance division. (If font size is not specified the gap is larger.)
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