right.. the idea was to insert the timestamp..
$time = time();
insert into table set field="somevalue", dateformat="d m Y", time="$time"
and then when you show it you do
$query
$r = mysql_fetch_array
echo date($r['dateformat'], $r['time'])
awfully shortend and stuff but you get the idea right?
when a user registers he gets to choose how to show the time..