UIView background image gets squashed

In my iPhone app I have a UIView with a tiled background image created via view.backgroundColor = [[UIColor alloc] initWithPatternImage:[UIImage imageNamed:@"IndexCard.png"]];

On my iOS3.1 device, when the view gets resized, the background image gets squashed - i.e. it tiles the same number of times but the height of each tile is reduced. Instead I would like each tile to stay the same size but the number of repeats to adjust according to the new view size. If I clear the background and then reset it the problem gets fixed, but that seems like a particular innefficient solution to the problem. On the iOS4.3 simulator it works correctly.

Here's the original image - 12 lines:

Here's what I'm seeing when I resize the view - it still has 12 lines:

Whereas here's what I'd really like to see - the background would be cropped to 5 lines:

Any ideas?

I found a much simpler solution:

view.contentMode = UIViewContentModeRedraw;
// instead of the default UIViewContentModeScaleToFill