Guarda, ho un pò modificato il tuo codice, non lo posso testare quindi non so se va, ma provalo:
Codice PHP:
<?php

    $get_seasons 
mysql_query("SELECT
                               * FROM
                               campionato
                               WHERE camppubbl = 1
                               ORDER BY SeasonNick"
,$connection) or die(mysql_error());

    if(
mysql_num_rows($get_seasons) < 1)
    {
        echo 
'[b]Non ci sono campionati nel database[/b]';
    }
    else
    {
        
?>
        <TD width=5>[img]../../immagini/blank.gif[/img]</TD>
        <?php
        $cont
=1;
        while(
$data mysql_fetch_array($get_seasons))
        {
            if(
$cont>5){
                
$cont=1;
                
?>
                <TD width=1> [img]../../immagini/black.gif[/img]</TD></TR>
                <TR>
                <?php
            
}
            
?>
            <TD width=1>[img]../../immagini/black.gif[/img]</TD>
            <TD><CENTER><A class="al" href="proxpartite.php?seasonid=<?=$data["SeasonID"]?>"> <FONT color="black">
            [b]<?=$data["SeasonNick"]?></FONT></A>[/B]</CENTER></TD>
            <?php
            $cont
++;
        }
        if(
$cont<5){
            while(
$cont<5){
                
$cont++;
                
?>
                <TD width=1>[img]../../immagini/black.gif[/img]</TD>
                <TD></TD>
                <?php
            
}
        }
        
?>
        <TD width=1> [img]../../immagini/black.gif[/img]</TD>
        <?php
    
}
?>