Starting with version 3.6 WordPress actively discourages from deregistering "critical" scripts in admin at all.

For posed scope (loading newer jQuery in specific part of admin) it would make more sense to load custom copy of jQueryrmally and use noConflict() on it right away to isolate it in own variable to be used in custom JS code.

Old andswer

deregister doesn work for you because WP concatenates scripts in admin area by default. So when you make jQuery load from elsewhere it falls apart.

You can disable concatenation to make it work (add conditionals as needed):

add_action( 'admin_init', 'jquery_admin' );
function jquery_admin() { global $concatenate_scripts; $concatenate_scripts = false; wp_deregister_script( 'jquery' ); wp_register_script( 'jquery', ( 'http://ajax.googleapis.com/ajax/libs/jquery/1/jquery.min.js' ), false, '1.x', true );
}

PS many thanks for trick with loading latest version from Google, I wasn aware of it :)