a bit heavy-handed, but this would work:
$order = array(10153,609,156,663,10128);
$result = mysql_query('SELECT DISTINCTROW priority, customerid FROM tblcustomers WHERE customerid IN(10153,609,156,663,10128)');
while ($row = mysql_fetch_assoc($result)) {$array[$row['customerid']] = $row;}
foreach ($order as $value)
{
$ordered_array[$value] = $array[$value];
}
print_r($ordered_array);