Css de yazdigim bir div iceriginde olan ifram IE normal aciyor ama diyer barzuerlerde duzgun cikmiyor.

Css yeni bashlamisham. Yazdigim menuda div icerisinde bir iframe kullanmisham.IE normal cikiyor ama Firefoxda normal gozukmuyor. Yardiminizi istiyorum. reset.css kullandim olmadi.
HELP

HTML kodu
<div id="header">
<iframe id="frame" src="menu.htm" scrolling=no marginheight="0" marginwidth="0" frameborder=0 width="509" height="59" ></iframe>
</div>

menu.css
#header{
width:1000px;
height:321px;
margin:0 auto;
background-image:url(images/bg.jpg);
background-position:top left;
background-repeat:no-repeat;
position:relative;

}
#meta a{
font-family:Tahoma;
color:#5B5B5B;
text-decoration:underline
}

#frame{
position:absolute;
top:275px;
#top:255px;
left:0px;
clear:both;
padding: 0 0 0 0px;
}
#menu li, #forum li{
list-style-type:none;
float:left;
margin:0 20px 0 0
}
#menu a, #forum a{
background-image:url(images/circle.gif);
background-position:0px 4px;
background-repeat:no-repeat;
font-family:Tahoma;
font-size:12px;
color:#323232;
text-decoration:none;
padding:0 0 0 12px
}
.title1{
background-image:url(images/title1.jpg);
background-position:top left;
background-repeat:no-repeat;
height:24px;
width:114px;
padding:12px 0 0 53px;
margin:0 0 0 9px;
display:inline;
font-family:Arial;
font-size:12px;
color:#FFFFFF;
font-weight:bold;
float:left
}
.contries{
width:170px;
display:block;
float:left;
padding:13px 0 15px 19px;
font-family:Arial;
font-size:12px;
}
.contries li{
list-style-type:none;
line-height:18px
}
.contries li a{
background-image:url(images/arrow.gif);
background-position:0px 3px;
background-repeat:no-repeat;
padding:0 0 0 11px;
color:#323232;
text-decoration:underline
}
.contries li a:visited{text-decoration:underline}
.contries li a:hover{text-decoration:none}