context.getImageData strangeness in IE9

Question

I'm using canvasContext.getImageData(0, 0, 1, 1).data to retrieve pixel information on an image. It works great in all browsers except IE9. At random times the pixel information is not available, it returns 0 instead of 255 which is expected.

I'm doing the getImageData code within the onload event of the image. The image src is defined after I created the onload function.

My current hack for IE9 is:

var image = new Image();

image.onload = function (e) {
        while (canvasContext.getImageData(0, 0, 1, 1).data[0] == 0) {
            canvasContext.drawImage(image, 0, 0, 200, 2);
        }
        // Do other important stuff
}

image.src = "someImage.png";

What happens is that the while loop runs about 30-60 times and then it finally retrieves the pixel information.

Any help on why this happens in IE9 would be great!

Thanks.