Vertically align sans-serif font precisely using jquery/css

问题

I'm trying to align a sans-serif headline precisely with menu elements in other div-Elements, so basically this:

Header
A B C

where A is aligned to the left end of the Header and C to the right end. I use float to distribute the -Elements and I compute the font-size to fit the header into the div width. The problem is that I use a sans-serif font. The problem is demonstrated in a fiddle

http://jsfiddle.net/ksuTQ/2/

<div id="Hideheader" class="Header" style="position: absolute;font-size:40pt;padding:0px;visibility: hidden;width:auto;height:auto;">HEADER</div>
<div id="header" class="Header">HEADER</div>
<div id="menubar" class="menubar">
    <div class="menubutton_left"><a href="#" id="WorkButton">A</a>
    </div>
    <div class="menubutton_middle"><a href="#" id="AboutButton">B</a>
    </div>
    <div class="menubutton_right"><a href="#" id="ContactButton">C</a>
    </div>  <span class="stretch"></span>

</div>

jscript

resizeHead("#Hideheader", "#header");

function resizeHead(p1, p2) {
    var fontsize = parseFloat($(p1).css("font-size"));
    var spacing = parseFloat($(p1).css("letter-spacing"));
    var initWidth = $(p1).width();
    initWidth = initWidth - spacing;
    var outWidth = $(p2).width();

    var s = outWidth / initWidth;
    s = fontsize * s;
    $(p2).css({
        "font-size": s
    });
}

CSS

div.Header {
    font-family:sans-serif;
    text-align:justify;
    white-space: nowrap;
}
div.menubar {
    text-align: justify;
    -ms-text-justify: distribute-all-lines;
    text-justify: distribute-all-lines;
    margin-bottom: 0px;
    position: relative;
}
div.menubutton_left, div.menubutton_middle, div.menubutton_right {
    vertical-align: top;
    display: inline-block;
    *display: inline;
    zoom: 1;
    width:60px;
}
div.menubutton_left {
}
div.menubutton_middle {
    text-align: center;
}
div.menubutton_right {
    text-align: right;
}
.stretch {
    border: 2px dashed #444;
    width: 100%;
    display: inline-block;
    font-size: 0;
    line-height: 0
}

How do I align the beginning of the A with the H of the header for a sans-serif font?