Firefox Positioning, Works On IE But Not Firefox Options

[lowridincrew]

ok when i made my layout code i did it on IE. It looks perfect on there but not on firefox.
Can you help me and also tell me what i did wrong?

CSS

CODE

div.contentTop {
height: 849px;
background-repeat: no-repeat;
background-position: top center;
background-image:url(http://i39.tinypic.com/28v87cp.jpg);
}


div.commentsModule ul.moduleList li.odd div.user {float:right;}
div.commentsModule ul.moduleList li.odd div.userComment {margin-left:0px; margin-right: 25%;}
div.commentsModule ul.moduleList li.odd div.comment {text-align:right;}
div.commentsModule div.moduleBody ul.moduleList li.odd div.userComment p.datePosted {text-align:right;}
div.blurbsModule h3 {display: none;}
div.interestsModule h3 {display: none;}
div.friendSpaceModule h3 {display: none;}

div.Sunvalley {position:absolute;
top:592px;
left:50%;
margin-left:-338px;}

div.messageme {
position:absolute;
top:429px;
left:50%;
margin-left:-250px;}
{position:static; margin:auto;}

HTML

CODE

<div class="Sunvalley">
<object height="387" width="673">
  <param name="allowScriptAccess" value="never" />
  <param name="allowNetworking" value="internal" />
  <param name="movie" value="http://www.youtube.com/v/QHVJuIhVvFQ&hl=en&fs=1&fmt=18&rel=1&autoplay=1&ap=%2526fmt%3D18&loop=1" />
  <param name="wmode" value="transparent" />
<embed type="application/x-shockwave-flash" allowScriptAccess="never" allowNetworking="internal" src="http://www.youtube.com/v/QHVJuIhVvFQ&hl=en&fs=1&fmt=18&rel=1&autoplay=1&ap=%2526fmt%3D18&loop=1" height="387" width="673" wmode="transparent" />
</object></div>

<div class="messageme">
<a href="http://www.msplinks.com/MDFodHRwOi8vbWVzc2FnaW5nLm15c3BhY2UuY29tL2luZGV4LmNmbT9mdXNlYWN0aW9uPW1haWwubWVz
2FnZSZmcmllbmRJRD00ODcxMDQyOSZNeVRva2VuPThiNTBlNGY0LTg2MGUtNGI5Yy1hMmVjLWVlMjgyN
IzOTJjNA=="><img src="http://s5.tinypic.com/a2tyyb.jpg" />
</a>
</div>