<?php 

// Rewrite Welcome to WordPress text in bottom right hand corner.
function daltonsutton_replace_footer_admin() {
    echo '<span id="footer-thankyou">&copy; '.date('Y').' <a href="'.get_bloginfo( 'url' ).'">'.get_bloginfo( 'name' ).'</a>. All rights reserved.</span>';
}
add_filter('admin_footer_text', 'daltonsutton_replace_footer_admin');

// Rewrite WordPress version in bottom right hand corner.
function daltonsutton_replace_footer_version() {
    echo 'WordPress v'.$GLOBALS['wp_version'];
}
add_filter('update_footer', 'daltonsutton_replace_footer_version', 9999);