There are 2 previous versions of this script.

// ==UserScript==
// @name           Facebook - Older posts bar always on bottom (Chrome and Firefox)
// @namespace      http://userscripts.org/users/23652
// @description    Older posts bar always on bottom
// @include        http://www.facebook.com/*
// @copyright      JoeSimmons
// @version        1.0.0
// @license        http://creativecommons.org/licenses/by-nc-nd/3.0/us/
// @require        http://sizzlemctwizzle.com/updater.php?id=75678
// ==/UserScript==

// Define GM_addStyle if it's not Firefox
if(GM_addStyle==="undefined" || typeof GM_addStyle==="undefined") {
    GM_addStyle = function(css) {
        var head = document.getElementsByTagName('head')[0], style = document.createElement('style');
        if(head) {
        style.type = 'text/css';
        try {style.innerHTML = css} catch(x) {style.innerText = css}
        head.appendChild(style);
		}
    };
}

GM_addStyle("#contentArea div.uiMorePagerAnchor { -moz-border-radius: 4px !important; position: fixed !important; bottom: 2px !important; left: 19% !important; width: 25% !important; background-color: #969696 !important; border-color: #000000 !important; z-index: 9999 !important; }  #contentArea div.uiMorePager * { color: #FFFFFF !important; }  .UIActionLinks.UIActionLinks_bottom.GenericStory_Info > a { float: right !important; }");