Need Help with IE 6 Compatibility

I discovered the other day that my site, Coupons To Your Inbox, looks messed up on IE 6:

IE 6 Screenshot



The logo transparency issue at the top has now been fixed. What I can't fix is the positioning of the opt-in box on the right. It's touching the main box on the left . There's supposed to be a space between them. How can I fix this without affecting how my site looks in newer browsers?

Here's the CSS:

body{
margin:0;
padding:0;
font:84% Helvetica, Arial, Sans-serif;
background:#ffffff;
color:#000000;
}

#container{
width:1000px;
margin:0 auto;
padding:0;
color:#000000;
}

#header{
width:1000px;
float:inherit;
margin-right:auto; 
margin-left:auto; 
padding:0;
background:#ffffff url(img/gradient-header.png) repeat-x;
}

[COLOR="Green"][B]#main{
width:600px;
float:left;
margin-left:80px; 
padding:0 0 15px 0;
background:#ffffff;
border-top:1px solid #cccccc;
border-right:1px solid #cccccc;
border-bottom:1px solid #cccccc;
border-left:1px solid #cccccc;
display:inline;
}[/B][/COLOR]

[COLOR="Red"][B]#right{
width:211px;
float:right;
margin-right:80px; 
padding:0 0 15px 0;
background:#ffffff;
border-top:1px solid #cccccc;
border-right:1px solid #cccccc;
border-bottom:1px solid #cccccc;
border-left:1px solid #cccccc;
}[/B][/COLOR]

#footer{
width:840px;
float:inherit;
margin-right:auto; 
margin-left:auto; 
padding:5px 0 5px 0;
font-size:0.9em;
text-align:center;
background:#e6ede7;
color:#000000;
}

Code (markup):

 

Remove the white space above the DOCTYPE. It's throwing IE 6 into Quirks Mode.

 

Thanks for the response, Dan. The space that you referred to contains a PHP script which works server-side. I heard that, as it works server-side, the space cannot be seen by browsers, hence they are not provoked into quirks mode. Is that not true?

More importantly, however, do you have an answer for my question above?

 

It's not true. Anything (whether it be an XML declaration, a Byte Order Mark, or even whitespace) above an XHTML DOCTYPE will force IE 6 into Quirks Mode.

If I were you, I'd modify that PHP script so that it doesn't create the white space. Even if it means calling it and the DOCTYPE on the same line in your editor.