Element drops down below float in IE6 [was: Easy one... for you at least!]

Question

Ok, has to do with Box Model or the chronic incapacities of those for Microsoft, from what i read. But this one is out my my my my my mind, or i am too tired to see.
Here is the CSS
margin:0;
padding:0;
line-height:130%
img {
display:block;
border:none;
body {
margin-left: 0px;
margin-top: 0px;
margin-right: 0px;
margin-bottom: 0px;
text-align:center;
background-color:#006699;
#mainDiv {
position:relative;
margin:auto;
width:954px;
background-image:url(francais/html/images/fond40.jpg);
#contenuTop {
padding-top:200px;
#left {
background-color:#CC6633;
float:left;
#right {
background-color:#FF9900;
height:500px;
margin-left:694px;
Here is the HTML
<div id="mainDiv">
  <div id="contenuTop">
  <div id="left"><img src="694x385/20040604-00098.jpg" alt="" width="694" height="385" /></div>
  <div id="right"><img src="francais/html/section40/page41/images/titre41.gif" alt="" width="260" height="69" /></div>
  </div>
</div>
Here are screenshots form Browser Lab. First from IE7 then from IE6. Why the hell is it different???? There is no padding, nor width of any kind anywhere???
[Subject line edited by moderator to indicate nature of question]

Answer 1

What does seem to work in IE6 is to give left div a width of 694px,   and right div a width of 260px, float right and margin-left: 0, and set the maindiv to width 954px.
I did not check this in IE7, since it really does not answer your question.  Just thought you might like to know in case no other solution is forthcoming.
E. Michael Brandt
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