Errore strano con if e elseif

[KaNnA]

ciao a tt
xchè se ho questo codice:

<?
$ora = date("G");
if (($ora >= "23") && ($ora <= "5")) {
    echo "<img src=\"img/mappe/Aragusnotte.jpg\" width=\"1001\" height=\"593\" border=\"0\" usemap=\"#Map\">";
} elseif (($ora >="6") && ($ora <="8")) {
    echo "<img src=\"img/mappe/Aragusalba.jpg\" width=\"1001\" height=\"593\" border=\"0\" usemap=\"#Map\">";
} elseif (($ora >="9") && ($ora <="17")) {
    echo "<img src=\"img/mappe/Aragusgiorno.jpg\" width=\"1001\" height=\"593\" border=\"0\" usemap=\"#Map\">";
} elseif (($ora >="18") && ($ora <="19")) {
    echo "<img src=\"img/mappe/Aragustramonto.jpg\" width=\"1001\" height=\"593\" border=\"0\" usemap=\"#Map\">";
} elseif (($ora >="21") && ($ora <="22")) {
    echo "<img src=\"img/mappe/Aragussera.jpg\" width=\"1001\" height=\"593\" border=\"0\" usemap=\"#Map\">";
}
?>

mi da sempre la mappa dell'alba?