setAccessoryViewしただけだとタップした時にaccessoryButtonTappedForRowWithIndexPathが発火しなくなるので以下のようにする。

// create cell
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    // call cell
    UITableViewCellFixed *cell = (UITableViewCellFixed *)[tableView dequeueReusableCellWithIdentifier:@"table_cell"];
    if (cell == nil) {// create cell
        cell = [[[UITableViewCellFixed alloc]initWithStyle:UITableViewCellStyleDefault reuseIdentifier:@"table_cell"] autorelease];
    }
    
    UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
    [button setFrame:CGRectMake(0, 0, 26, 26)];
    [button setBackgroundImage:[UIImage imageNamed:@"arrow.png"] forState:UIControlStateNormal];
    [button setBackgroundColor:[UIColor clearColor]];
    [button addTarget:self action:@selector(accessoryButtonTapped:withEvent:) forControlEvents:UIControlEventTouchUpInside];
    [cell setAccessoryView:button];
    return cell;
}
- (void)accessoryButtonTapped:(UIControl *)button withEvent:(UIEvent *)event
{
    NSIndexPath *indexPath = [self.tableView indexPathForRowAtPoint:[[[event touchesForView: button] anyObject] locationInView:self.tableView]];
    if (indexPath == nil) {
        return;
    }
    [self.tableView.delegate tableView: self.tableView accessoryButtonTappedForRowWithIndexPath:indexPath];
}