CSS positioning problem with IE 6

Ok, forgive my ignorance but I’m building my first website using purely CSS and need some help getting it to look as expected in IE 6. Here’s a link to the basic template page:

[url]http://www.olivia-temple.com/test/home.html[/url]

And here’s the CSS for the positioning divs:

[CODE]#left_column {
float: left;
width: 340px;
z-index:2;
}

#right_column {
position: relative;
margin-left: 340px;
z-index:1;
}

#content {
position:absolute;
width: 100%;
overflow: auto;
}

#navbar {
position:absolute;
top:228px;
left:50px;
width: 200px;
}

#heading_div {
height: 130px;
width: 100%;
border-bottom-width: 2px;
border-bottom-style: solid;
border-bottom-color: #563400;
}

#header_text {
position:absolute;
top: 55px;
right: 75px;
text-align: left;
width: 130px;
}

#header_logo {
position:absolute;
top: 0px;
right: 0px;
}

#main_content {
max-width: 600px;
width: expression(this.width > 600? “600px”: “auto” );
padding: 20px;
}[/CODE]

Now is my CSS bad or is it just that IE 6 has trouble interpreting column layouts, and if so is there a hack I can use? Please help, this is driving me mad!

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