Horizontal UIScrollView in a UITableViewCell

Horizontal UIScrollView in a UITableViewCell

I'm trying to create a simple scrollView inside a tableview cell. Just
like on app store, but with simpler scrolling.
The scrollview is showing up but its not scrolling at all. I've tried
whole first page on google and many stackoverflow questions, can't seem to
find what I'm doing wrong.
if (indexPath.row==0) {
// Clearing out cell background
[cell setBackgroundColor:[UIColor clearColor]];
[cell.contentView setBackgroundColor:[UIColor clearColor]];
// Imageviews for scrollview
UIImageView *imageview1 = [[UIImageView alloc]
initWithFrame:CGRectMake(0,0,320,123)];
UIImageView *imageview2 = [[UIImageView alloc]
initWithFrame:CGRectMake(320,0,320,123)];
imageview1.image = [UIImage imageNamed:@"flash2.png"];
imageview2.image = [UIImage imageNamed:@"IMG_2458.JPG"];
// setting up scrollview
self.scrollViewHeader = [[UIScrollView alloc]
initWithFrame:CGRectMake(0,0,320, 123)];
self.scrollViewHeader.scrollEnabled = YES;
self.scrollViewHeader.delegate = self;
[self.scrollViewHeader setUserInteractionEnabled:YES];
[self.scrollViewHeader setContentSize:CGSizeMake(320, 123)];
[self.scrollViewHeader addSubview:imageview1];
[self.scrollViewHeader addSubview:imageview2];
[cell.contentView addSubview:self.scrollViewHeader];
}
else{
// Normal table cells.
...
}
Thanks in advance for your answers.