Linking thumbnails does not work, since clicking on them only opens the image viewer. This is quite a problem, since you can't link galleries or easily link multiple images because of this.
The code just reads the IMG tag not the URL. The best we can do, is get an addon that will automatically make the thumb from a big image instead of resizing it.
There's no mod like that... Well, it's not something hard to make, but they didn't make it because it would cause an extreme crazy load to the server. Serving thumbnail (multiple small files) requires SSDs
I know what causes this, the question is how to fix it. :P
Best would be if the script ignores images below the resizeable dimensions - so thumbs won't be affected by it to begin with. ;)