IE positioning problems

Newbie – Used the validator and came up only with some color warnings.

Go to [url]http://www.hairpower.com[/url] to see problem. The right and left sides used to align about a month ago. Now, they don’t.

Looks fine in Firefox.

Any thoughts? .strongsilent is the area that’s falling out of alignment. Here’s the CSS:

body {
background-color: #000000;
}
ul#mainNav {
padding-top: 3px;
list-style: none;
margin-left:310px;
margin-top:48px;
font-size:12px;
}
#mainNav a{
color:#000000;
font-size: 11px;
text-decoration: none;
padding-left:30px;
font-weight: bold;
height: 23x;
display: inline;
}
#mainNav a:hover{
color:#FFFFFF;
font-size: 11px;
text-decoration:underline;
padding: 2px 10px 0px 12px;
font-weight: bold;
height: 23px;
display: inline;
}
.toplogo {
background-image:url(topnav.jpg);
background-repeat: no-repeat;
background-position: center;
height: 104px;
}
#wrapper {
background-image:url(gradbknd.jpg);
background-repeat:no-repeat;
width: 780px;
height: auto;
margin-right: auto;
margin-left: auto;
position:relative;
background-color: #FFFFFF;
}
.welcome {
margin-left:0px;
margin-top:0px;
float:left;
}
.strongsilent {
float:right;
}
.h1 {
float:right;
margin-top:10px;
margin-right:18px;
font-family:”Times New Roman”, Times, serif;
font-size:13px;
font-weight:bold;
}
.h2 {
float:left;
margin-top:90px;
margin-left:40px;
font-family:”Times New Roman”, Times, serif;
font-size:13px;
font-weight:bold;
position:absolute;
line-height:18px;
display:inline;
}
.flash {
float:left;
margin-left:33px;
position:absolute;
display:inline;
margin-top:350px;
}
.righttext {
float:right;
margin-top:50px;
margin-right:10px;
font-family:”Times New Roman”, Times, serif;
font-size:13px;
color:#FFFFFF;
position:absolute;
left: 550px;
top: 218px;
}
.righttext2 {
float:right;
margin-top:80px;
margin-right:10px;
font-family:”Times New Roman”, Times, serif;
font-size:13px;
color:#FFFFFF;
position:absolute;
left: 550px;
top: 268px;
}
.righttext3 {
float:right;
margin-top:80px;
margin-right:10px;
position:absolute;
left: 550px;
top: 308px;
}

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