ImageViews with remote images not showing as Retina

Using SDK 3.5.1 currently

I have some remotely hosted images that I am loading into my ImageViews. I have hires:true already set.

Here is the code I'm using:

var hasattachesThumbIcon = Ti.UI.createImageView({
                    width:96,
                    height:'auto',
                    top:6,
                    bottom:6,
                    right:10,
                    image:hasattachesThumb,
                    defaultImage:'/icons/placeholder_big.png',
                    hires:true,               
          });

I think the issue is that I'm not explicitly setting the height of the image. The reason is that the images are of all different sizes and aspect ratios, my only requirement is that they should fit into a block measuring 96 pixels, so i've set it as such.

Any ideas?

Thanks!