Centrare l'intestazione del sito in css con Explorer 5.5

<div id="container">
   <div id="header">
   </div>
   <div id="corpo">
       <div id="content">
       </div>
       <div id="menu">
       </div>
   </div>
</div>
<div id="footer">
</div>

body {
	margin: 0;
	padding: 0;
	text-align: center;
	background: #FF0000 url(../immagine.jpg) repeat-x center bottom;
}

#container {
	width: 800px;
	margin: auto;
	background-position: center;
	background-repeat: repeat-y;
	background-image: url(../immagine.jpg);
	text-align: left;
}

#header {
	position:relative;
	display: block;
	width: 800px;
	height: 223px;
	background: url(../immagine.jpg);
}

#corpo {
	width: 800px;
	float: right;
	display: inline;
}

#content {
	float: right;
	display: inline;
	width: 550px;
	background: transparent url(../immagine.jpg) no-repeat;
	color: #000;
}

#menu {
	float: right;
	display: inline;
	width: 180px;
	background: transparent;
	color: #000;
	font: italic bold 13px Georgia, "Times New Roman", Times, serif;
	margin-right: 15px;
	letter-spacing: -2.5px;
	word-spacing: 2px;
	}
	
#footer{	
	height: 210px;
	background-image: url(../immagine.jpg);
	clear: both;
}

#header {
	float: right;
	display: inline;
	width: 800px;
	height: 223px;
	background: url(../immagine.jpg);
}