iphone sdk: Can’t reuse cell with viewWithTag (can not setText to reused labels)

[SimpleCode]

This is my cellForRowAtIndexPath function. I could not get the setText to the label to work. Can you please help me out?

// Customize the appearance of table view cells. - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {

static NSString *CellIdentifier = @"Cell";
UILabel *messageLabel = nil;
int row = [indexPath row];
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {

        cell = [[UITableViewCell alloc] initWithFrame:CGRectMake(0, 0, 320, ROWHEIGHT) reuseIdentifier:CellIdentifier];
        messageLabel = [[UILabel alloc] initWithFrame:CGRectMake(60, 5, 240, 60)];
        [messageLabel setFont:[UIFont fontWithName:@"ArialMT" size:12]];
        [messageLabel setTextColor:[UIColor blackColor]];
        [messageLabel setBackgroundColor:[UIColor clearColor]];
        [messageLabel setNumberOfLines:3];
        [messageLabel setLineBreakMode:UILineBreakModeWordWrap];
        [messageLabel setTag: messageTag];

        [cell.contentView addSubview:messageLabel];

}
else{
        messageLabel = (UILabel *)[cell viewWithTag:messageTag];

}

[messageLabel setText:[[[aSingleton wallItemArray] objectAtIndex:row] message]];

NSLog(@" -- > at row %d, message: %@", row, [[[aSingleton wallItemArray] objectAtIndex:row] message]);

return cell;
}