ทำ Transaction [INTERSOLV][ODBC Informix driver]Optional feature not implemented., SQL s Error...Warning: odbc_autocommit() [function.odbc-autocommit]:

$conn=odbc_connect('xxx','user','pass') or die ("Can not connect server");
odbc_autocommit($conn,false); 
$sql = "insert into employee (id, name) values ('$id', '$name')";
$query = odbc_exec($conn, $sql);
if ($query) {
     odbc_commit($conn);
     echo "OK";
} else {
     odbc_rollback($conn); 
     echo "Error";
}
closeDB($conn);