This is an issue that I have just come across.
I was using a png that was 3000 px h and 1 px wide then squashing down and stretching wide in the xml.
On the xml layout designer view in eclipse it is shown fine,
however on device it does not.
This is weird!
I have no idea why but it seems that there is a max image height of 2000px in the android compiler/renderer or something? My fix was to make the image at 2000px height.