Non credo...

ti posto tutto lo script del menù che con mozilla e IE vedo allo benissimo stesso modo.

codice:
<script type='text/javascript'>

function Go(){return}

</script>
<script type='text/javascript'>

	var NoOffFirstLineMenus=10;			// Number of first level items
	var LowBgColor='white';			// Background color when mouse is not over
	var LowSubBgColor='white';			// Background color when mouse is not over on subs
	var HighBgColor='yellow';			// Background color when mouse is over
	var HighSubBgColor='black';			// Background color when mouse is over on subs
	var FontLowColor='black';			// Font color when mouse is not over
	var FontSubLowColor='black';			// Font color subs when mouse is not over
	var FontHighColor='white';			// Font color when mouse is over
	var FontSubHighColor='white';			// Font color subs when mouse is over
	var BorderColor='black';			// Border color
	var BorderSubColor='black';			// Border color for subs
	var BorderWidth=1;				// Border width
	var BorderBtwnElmnts=1;			// Border between elements 1 or 0
	var FontFamily="arial,comic sans ms,technical"	// Font family menu items
	var FontSize=9;				// Font size menu items
	var FontBold=1;				// Bold menu items 1 or 0
	var FontItalic=0;				// Italic menu items 1 or 0
	var MenuTextCentered='left';			// Item text position 'left', 'center' or 'right'
	var MenuCentered='center';			// Menu horizontal position 'left', 'center' or 'right'
	var MenuVerticalCentered='top';		// Menu vertical position 'top', 'middle','bottom' or static
	var ChildOverlap=0;				// horizontal overlap child/ parent
	var ChildVerticalOverlap=0;			// vertical overlap child/ parent
	var StartTop=58;				// Menu offset x coordinate
	var StartLeft=0;				// Menu offset y coordinate
	var VerCorrect=0;				// Multiple frames y correction
	var HorCorrect=0;				// Multiple frames x correction
	var LeftPaddng=3;				// Left padding
	var TopPaddng=2;				// Top padding
	var FirstLineHorizontal=1;			// SET TO 1 FOR HORIZONTAL MENU, 0 FOR VERTICAL
	var MenuFramesVertical=1;			// Frames in cols or rows 1 or 0
	var DissapearDelay=1000;			// delay before menu folds in
	var TakeOverBgColor=1;			// Menu frame takes over background color subitem frame
	var FirstLineFrame='navig';			// Frame where first level appears
	var SecLineFrame='space';			// Frame where sub levels appear
	var DocTargetFrame='space';			// Frame where target documents appear
	var TargetLoc='';				// span id for relative positioning
	var HideTop=0;				// Hide first level when loading new document 1 or 0
	var MenuWrap=1;				// enables/ disables menu wrap 1 or 0
	var RightToLeft=0;				// enables/ disables right to left unfold 1 or 0
	var UnfoldsOnClick=0;			// Level 1 unfolds onclick/ onmouseover
	var WebMasterCheck=0;			// menu tree checking on or off 1 or 0
	var ShowArrow=1;				// Uses arrow gifs when 1
	var KeepHilite=1;				// Keep selected path highligthed
	var Arrws=['tri.gif',5,10,'tridown.gif',10,5,'trileft.gif',5,10];	// Arrow source, width and height

function BeforeStart(){return}
function AfterBuild(){return}
function BeforeFirstOpen(){return}
function AfterCloseAll(){return}


Menu1=new Array("Home","http://a.it","",0,20,60);

Menu2=new Array("Società","#","",7,20,80);
	Menu2_1=new Array("A","blank.htm","",0,35,170);
	Menu2_2=new Array("B","blank.htm","",0,35,170);
	Menu2_3=new Array("C","blank.htm","",0,35,170);
	Menu2_4=new Array("D","blank.htm","",0,35,170);
	Menu2_5=new Array("E","blank.htm","",0,35,170);
	Menu2_6=new Array("F","blank.htm","",0,35,170);
	Menu2_7=new Array("G","blank.htm","",0,35,170);						

Menu3=new Array("A","blank.htm","",5,20,80);
	Menu3_1=new Array("A","blank.htm","",4,20,150);
		Menu3_1_1=new Array("A","blank.htm","",0,20,150);
		Menu3_1_2=new Array("B","blank.htm","",0,20,150);
		Menu3_1_3=new Array("C","blank.htm","",0,20,150);
		Menu3_1_4=new Array("D","blank.htm","",0,20,150);
	Menu3_2=new Array("A","blank.htm","",2);
		Menu3_2_1=new Array("A","blank.htm","",0,20,150	
		Menu3_2_2=new Array("B","blank.htm","",0,20,150	
	Menu3_3=new Array("C","blank.htm","",0);
	Menu3_4=new Array("D","blank.htm","",0);
	Menu3_5=new Array("E","blank.htm","",0);		

Menu4=new Array("A","blank.htm","",3,20,78);
	Menu4_1=new Array("A","blank.htm","",0,20,180);
	Menu4_2=new Array("B","blank.htm","",0);
	Menu4_3=new Array("C","blank.htm","",0);

Menu5=new Array("A","javascript:top.location.href='blank.htm'","",2,20,98);
	Menu5_1=new Array("A","blank.htm","",0,20,140);
	Menu5_2=new Array("B","blank.htm","",0,20,140);	
	
Menu6=new Array("A","javascript:top.location.href='blank.htm'","",7,20,140);
	Menu6_1=new Array("A","blank.htm","",0,20,140);
	Menu6_2=new Array("A","blank.htm","",0,20,140);	
	Menu6_3=new Array("B","blank.htm","",0,20,140);
	Menu6_4=new Array("C","blank.htm","",0,20,140);	
	Menu6_5=new Array("D","blank.htm","",0,20,140);
	Menu6_6=new Array("E","blank.htm","",0,20,140);	
	Menu6_7=new Array("F","blank.htm","",0,20,140);
	
Menu7=new Array("A","javascript:top.location.href='blank.htm'","",0,20,110);	
Menu8=new Array("B","javascript:top.location.href='blank.htm'","",0,20,110);	
Menu9=new Array("C","javascript:top.location.href='blank.htm'","",0,20,80);	
Menu10=new Array("D","javascript:top.location.href='blank.htm'","",0,20,120);	
	
			
</script>
<script type='text/javascript' src='menu_com.js'></script>
<noscript>Your browser does not support script</noscript>
Questo sta nell'body mentre nel head c'è l'onresize che ho scritto sopra.