I have seen this bug many times, whenever you have used float with horizontal margin IE doubles the margin.
Example:
.banner{
float:left;
margin-left:10px;
}
IE will show 20px margin on the left side, it doubles the margin.
Simple fix for this bug is use display property to inline.
Fix:
.banner{
float:left;
margin-left:10px;
display:inline;
}
