Div floats

Hej derude!

Jeg sidder og leger med opsætning af layers.
Legen foregår her: http://knudsen.2lderlund.dk/
Men jeg kan ikke få den grå div nederst til højre at blive lige så høj som den venstre del af gallery div'en. Den følger ikke med.

Her er stylesheetet:

html, body {
    margin: 0;
    padding: 0;
}

body {
    background-image: url(../layout/mainbg.gif);
    background-repeat: repeat-x;
    background-position: top;
    margin-top:0;
}

p {
    font-family:Tahoma, Verdana;
    font-size:12px;
    padding-left: 4px;
    }
.doegnvagt {
    font-family:Tahoma, Verdana;
    font-size:25px;
    font-weight:bold;
    color:#FFFFFF;
    text-align:center;
    }   

.gallery {   
    font-family:Tahoma, Verdana;
    font-size:9px;
    font-weight:bold;
    color:#666666;
    padding-top: 1px;
    padding-left: 4px;
    text-align:left;
    }   

.hidden {
    display: none;
}

#bgcontainer {
    width:840px;
    margin: auto;
    margin-top: 15px;
    background-image:url(../layout/logolarge.jpg);
    background-repeat:no-repeat;
    background-position:right top;
    z-index: 1;
}

#pagecontainer {
    width:727px;
    float:left;
    border-style:solid;
    border-width: 1px;
    border-color:#8c8c8c;
    z-index: 2;
}

#header {
    height: 85px;
    background-image:url(../layout/logo.gif);
    background-repeat:no-repeat;
    background-position:left bottom;
    margin-bottom: 15px;
    text-align:right;
}

/* Main Navigation */

#main-nav { height: 42px; }
#main-nav {
    background-image:url(../layout/menu_bg.gif);
    background-repeat:repeat-x;
    }

#main-nav dl { margin: 0; padding: 0; }

/* IE5 Mac Hack \*/
#main-nav { padding-left: 11px; }
/*/
#main-nav { padding-left: 11px; overflow: hidden; }
/* End Hack */

#main-nav dt { float: left; }

#main-nav dt a {
    display: block;
    height: 0px !important;
    height /**/:42px; /* IE 5/Win hack */
    padding: 42px 0 0 0;
    overflow: hidden;
    background-repeat: no-repeat;
}

#main-nav dt a:hover {
    background-position: 0 -42px;
}

#main-nav dt#home,
#main-nav dt#home a { width: 29px; background-image: url(../images/nav/home.gif); }

#main-nav dt#about,
#main-nav dt#about a { width: 48px; background-image: url(../images/nav/about.gif); }

#sidebar-a {
    background-color:#0079c2;
    filter: Alpha(Opacity=20);
    float: right;
    width: 155px;
    height: 278px;
}

#sidebar-a .padding {
    padding: 0px;
}

#content {
    margin-right: 155px;
    line-height: 18px;
}

#content .padding {
    padding: 0px;
}

    #imagecontainer {
    width: 360px;
    height: 270px;
    float:left;
    margin: 4px;
    }

    #commentcontainer {
    width: 190px;
    height: 248px;
    float:right;
    margin: 4px;
    text-align:left bottom;
    }
   
    #imgnavigation {
    height: 22px;
    width: 50px;
    float:right;
    text-align:right;
    margin-right: 4px;
    }

#divider {
    clear: both;
    background-image:url(../layout/currentgal_bg.jpg);
    background-repeat:repeat-x;
    height: 13px;
}

#sidebar-b {
    background-color:#ebebeb;
    float: right;
    width: 155px;
    height:100%;
    line-height: 18px;
}

#sidebar-b .padding {
    padding: 0px;
}

#gallery {
    margin-right: 155px;
    line-height: 18px;
}

#gallery .padding {
    padding: 0px;
}

    #thumbcontainer {
   
    float:left;
    width: 137;
    height: 103;
    margin-left: 4px;
    margin-top: 4px;
    }

#footer {
    clear: both;
    background:#999999;
    background-image:url(../layout/bottom_bg.jpg);
    background-repeat:repeat-x;
    height: 14px;
    text-align:center;
    font-family:Tahoma, Verdana;
    font-size:10px;
    font-weight:normal;   
    color:#000000;
}

Er der nogen der har et forslag?