Affichage Opera

Bonjour,
La page suivante :
s'affiche correctement dans IE et Firefox. Dans Opera, la div placée à droite du menu de navigation gauche est décalée vers le bas.
Pourtant, tout est configuré en %, sauf le menu de navigation (180px)
Voici le code source :

/* CSS Document */

html,body {
	font: 0.8em Verdana, Arial, Helvetica, sans-serif;
	margin: 0px;
	padding: 0px;
	background: #dcdae9;
	scrollbar-base-color: #dcdae9
}
#container1 {
	width: 90%;
	border-right: 15px solid #847DB1;
	border-bottom: 2px solid #847DB1;
	border-left: 15px solid #847DB1;
	margin-top: 0px;
	margin-right: auto;
	margin-left: auto;
	background: #FFFFFF;
	height: auto;
	border-top: 2px solid #847DB1;
}
#leftbanner {
	background: #FFFFFF url(images/portrait_reconstitue.gif) no-repeat left top;
	float: left;
	height: 159px;
	width: 209px;
}
#rightbanner {
	background: url(images/banniere_dc.gif) no-repeat right center;
	height: 159px;
	width: auto;
}
div#topnav {
	height: 30px;
	width: 100%;
	border-top: 1px solid #847db1;
	border-bottom: 1px solid #847db1;
	background-color: #FFFFFF;
	text-align: center;
	font-size: 0.9em;
}
div#topnav
 ul {
	margin: 0px;
	padding: 0px;
	font-family: Verdana, Arial, Helvetica, sans-serif;
	line-height: 30px;
	white-space: nowrap;
	font-weight: bold;
	color: #cc4400;
	font-size: small;
}
div#topnav li {
    list-style-type: none;
    display: inline;
}
div#topnav li a {
	text-decoration: none;
	padding: 7px 10px;
}
div#topnav li a:link {
    color: #cc4400;
}
div#topnav li a:visited {
    color: #cc4400;
}
div#topnav li a:hover {
	color: #FFFFFF;
	background-color: #9690bc;
}
#container2 {
	width: 100%;
	height: 420px;
	background: #FFFFFF url(images/degradegrispagesinternes.gif) repeat-y;
}
#leftnav {
	background: url(images/degradegrispagesinternes.gif) repeat-y;
	float: left;
	width: 180px;
	margin: 0px;
	padding: 30px 0px 0px;
	clear: both;
	text-align: left;
	font-size: 0.8em;
	display: block;
	line-height: 1.7em;
	height: 140px;
	border: Aucune;
}
#leftnav ul {
	margin: 0px;
	padding: 0px;
	list-style: none;
}
#leftnav li {
	padding: 0.5em 0em 0em 0.5em;
	border-bottom: 1px solid #847DB1;
}
#leftnav a {
	text-decoration: none;
}
#leftnav a:link {
	color: #000066;
}
#leftnav a:visited {
	color: #000066;
}
#leftnav a:hover {
	color: #A62900;
	border-color: rgb(98%,48%,40%);
	font-weight: bold;
}
#main {
	height: 420px;
	margin: 0px;
	font-size: 9px;
	text-align: left;
	padding: 0px 0px 0px 30px;
	overflow: auto;
	color: #A62900;
	background: #FFFFFF;
}
h2 {
	color: #A62900;
	font-weight: bold;
	font-size: small;
	line-height: 0.7em;
	padding-top: 1px;
	height: 20px;
}
p {
	color: #343050;
	line-height: 1.5em;
	font-weight: normal;
}
h3 {
	font-size: 1.7em;
	color: a62900;
	height: 1.4em;
	border-bottom: 1px solid #a62900;
	width: 50%;
	background: url(/CARON/images/losange.gif) no-repeat left center;
	padding-left: 20px;
	text-indent: 10pt;
}
.titremain {
	color: #000066;
	font-size: 1.7em;
	font-weight: bold;
	line-height: 2.5em;
	background: url(images/losange.gif) no-repeat left top;
	width: 60%;
	border-bottom: 1px solid #a62900;
	text-indent: 0pt;
	height: 30px;
	padding-bottom: 7px;
	text-align: left;
	padding-left: 20px;
	margin-top: 10px;
}
td {
	border: none;
}
tr {
}
th {
	border-right: 1px solid #A62900;
	border-bottom: 1px solid #A62900;
	border-top: none;
	border-left: none;
	line-height: 1.5em;
}

Y a-t-il un remède ?
Merci d'avance.

Je me permets de relancer ma question...