Verschobene Navigation im IE

[kwxllx]

Hallo,
habe eine Seite "übernommen", also bisher das wenigste selbst geschrieben, und wurde jetzt darauf aufmerksam gemacht, dass die Navigation im IE vollkommen verschoben ist. Unter Firefox und Chrome läuft sowohl am PC als auch mobil alles sauber.

Hier der Header:

<!-- Header -->  
    <div class="center">  
        <div class="header">  
            <a class="logo" href="../"><img src="../html/images/project/logo.png" alt="" /></a>  
                    <?php require_once TEMPLATE_PROJECT_PATH.'includes/navigation.inc.php'; ?>  
            <?php  
            $englishClass = getPage(getConfigId('home', 'en'));  
            $germanClass = getPage(getConfigId('home', 'de'));  
  
            $enClass ='';  
            $enClassOff = '';  
            if(in_array($englishClass->getId(), $englishClass->getPath(true)))  
            {  
                $enClass = ' class="active"';  
               # $denClassOff = '_off';  
            }  
            $deClass ='';  
            $deClassOff = '';  
            #var_dump($germanClass->getPath(true));  
            if(in_array($germanClass->getId(), $germanClass->getPath(true)))  
            {  
                $deClass = ' class="active"';  
                #$enClassOff = '_off';  
            }  
            ?>  
  
            <div style="position: relative">  
            <ul id="lang_nav">  
     <li><a href="<?php echo $germanClass->genUrl(); ?>" title="deusch"<?php  echo $deClass; ?>><img src="../html/images/project/de<?php echo $deClassOff; ?>.png" alt="de" /></a>  
  
</li>  
  
  
     <li><a href="<?php echo $englishClass->genUrl(); ?>" title="english"<?php  echo $enClass; ?>><img src="../html/images/project/gb<?php echo $enClassOff; ?>.png" alt="en" /></a></li>  
     <li><a href="xxxxx" target="_blank"><img src="../html/images/project/fb.png" alt="fb" /></a></li>  
            </ul>  
            </div>  
        </div>  
    </div>

Die Navigation:

<div class="menu">  
  
				<div class="menu_inner">  
					<ul>  
					<?php  
	$navigation = getMainNavigation();  
	if (empty($navigation) || !is_array($navigation))  
	{  
		return null;  
	}  
    foreach ($navigation as $key=>$main_page)  
    {  
  
    	if($main_page->getHide() && !isAdmin())  
        {  
            continue;  
        }  
  
        $css_classes = 'page-item';  
  
        $path = ($main_page->getPath());  
        if(($main_page->isCurrent() || $main_page->isPathCurrent()) || (!$main_page->isCurrent() && count($path)==1 && $main_page->getId() == getConfigId('home')))  
        {  
            $css_classes .= ' current_page_item';  
        }  
        $css_classes .= ' menu-item-'.$main_page->getId();  
  
        $subpages = get_childs_class($main_page->getId());  
  
  
        $levelLink = $main_page->genUrl();  
  
        if(getConfigId('PORTFOLIO') === $main_page->getId() && !empty($subpages) && is_array($subpages))  
        {  
			$levelLink = $subpages[0]->genUrl();  
        }  
  
        ?>  
            <li class="<?php echo $css_classes; ?>">  
							<a href="<?php echo $levelLink; ?>" title="<?php echo $main_page->getTitle(); ?>"  
                			tabindex="<?php echo $key+10; ?>"><?php echo $main_page->getNavigationTitle(); ?></a>  
  
<?php  
            if( $main_page->getId() === getConfigId('home'))  
            {  
                continue;  
            }  
            if(empty($subpages) || !is_array($subpages) || false !== $main_page->getMain() || false !== $main_page->getHideChilds())  
            {  
            	continue;  
            }  
?>  
<div class="childrenWrapper">  
				<ul class="children">  
<?php  
			foreach($subpages as $subpage)  
            {  
				$css_classes = 'page_item';  
				if($subpage->isCurrent() || $subpage->isPathCurrent())  
				{  
					$css_classes .= ' current_page_item';  
				}  
				$css_classes .= ' menu-item-'.$subpage->getId();  
?>  
					<li class="<?php echo $css_classes; ?>">  
                    	<a href="<?php echo $subpage->genUrl(); ?>" title="<?php echo $subpage->getTitle(); ?>">  
                    	<?php echo $subpage->getNavigationTitle(); ?>  
                    	</a>  
                    </li>  
<?php  
                }  
?>  
				</ul>  
				</div>  
			</li>  
<?php  
  
    }  
?>  
					</ul>  
				</div>  
			</div>

Die entsprechenden Teile der CSS-Datei:

.center {  
	margin: 0 auto;  
	max-width: 970px;  
    min-width: 940px;  
    width: 950px;  
	overflow:visible;  
}  
  
.header {  
    margin: 0 auto 50px;  
    height: 66px;  
    width: auto;  
}  
  
#lang_nav {  
    position: absolute;  
    right: 20px;  
    top: 28px;  
    width: 150px;  
    text-align: right;  
    border: none;  
}  
  
#lang_nav li{  
    display: inline !important;  
    border: none;  
  
}  
  
#lang_nav li a img{  
    border: none;  
  
}  
#lang_nav li a.active img{  
    border: none;  
}  
  
.menu {  
    height: auto;  
    margin: 0px 0 0;  
    padding: 0;  
}  
  
.menu .menu_inner {  
	margin-top: 24px;  
	height:66px;  
}  
  
.menu ul {padding: 4px 0 0 20px ;z-index: 100000;/*overflow:hidden*/}  
.menu ul .childrenWrapper {position:absolute;z-index:100000; min-width:250px; top: 45px; left:0px;display:none;}

Das Ganze läuft unter OpenEngine.
Über Hilfe wäre ich sehr, sehr dankbar.