UNIX_TIMESTAMP problem.

Denne kode fejler.

$sql = "insert into $mysql_db_table SET ";
for($i = 0; $i < count($felt); $i++) {
  if($felt[$i] == "create_date") { $_POST{$felt[$i]} = UNIX_TIMESTAMP('0'); }
  $sql .= "`$felt[$i]` = '" . $_POST[$felt[$i]] . "' ";
  if($i != (count($felt)-1)) {
        $sql .= ", ";
    }
}
mysql_query($sql) or die(mysql_error());

Fejlen er:

Fatal error: Call to undefined function: unix_timestamp() in /var/www/epoxy/web3/scan-vikardk/docs/admin/create_update.php on line 26


Nogle der ved hvorfor?