php i mysql4 contra mysql5

Hej.
Min host har opgraderet fra mysql4 til mysql 5.
Nogle af mine scripts kører udmærket men der er også nogle der bare ikke funker. Bl a :

<?php

            echo "<table width='320' border='0' cellspacing='0' cellpadding='2'>";
            echo "<tr>";
            echo "<td width='50'> </td>";
            echo "<td width='195'><span class='headerblack'>Rider</span></td>";
            echo "<td width='80' align='left'><span class='headerblack'>Stage</span></td>";
            echo "</tr></table>";

$wins = mysql_query("SELECT

sta.year AS year,
sta.name AS name,
sta.stage AS stage,
sta.etape AS etape,
sta.reason AS reason,
aa.year AS aayear,
aa.nummer AS nummer,
aa.navn AS navn,
ryt.id AS id,
ryt.flags AS flags,
ryt.name AS ryttername,
ryt.country AS country


FROM
    out AS sta
    INNER JOIN ryttere AS ryt

    INNER JOIN
    alleaar AS aa
ON
    aa.navn = ryt.id

WHERE sta.year=$aar AND sta.name = ryt.id AND aa.year=$aar

GROUP BY
    ryt.id

ORDER BY stage ASC, nummer ASC

");

while($w=mysql_fetch_array($wins)){

$ryttername = $w['ryttername'];
if( strlen($ryttername) > 30 )
{
$ryttername = substr($ryttername,0,30).'..';
}
    $number = $number + 1;
    if($number % 2 == 0){$color="#F2F2F2";}else{$color="#F8F9C1";}

            echo "<table width='320' border='0' cellspacing='0' cellpadding='2'><tr bgcolor='$color'>";
          echo "<td width='20' align='left' valign='top'><img src=$w[flags] width='10' height='10' border=0></td>";
            echo "<td width='25' align='right'  valign='bottom'>$w[nummer]</td>";
            echo "<td width='210' align='left' valign='bottom'><a href=http://www.tourfacts.dk/root/tour_de_france_riders.php?id=$w[id] class='link2'>". $ryttername ."</a></td>";
            echo "<td width='20' align='right'  valign='bottom'>$w[etape]</td>";
            echo "<td width='35' align='right'  valign='bottom'><font size='1'>($w[reason])</font></td>";
            echo "</tr></table>";

}

$number = 0;

?>

Skulle der mon være en der kan fortælle mig hvad der gør at det ikke virker?