A little while ago, there was a topic on Russian Military Registrations which has now been archived. You can find it here:
New Russian Military Registrations (by FYODOR Jul 9 2011 in Aviation Photography)
In that thread we discussed the way that Airliners.net displays Russian registrations based on the Bort code with the colour. Back then we said:
"Originally the colour was to be written in lower case, but the upload system automatically converts this to capital letters now, so capitals are effectively the official way to do it!"
We accepted this because the upload page forces the text into capitals. That is still true, but we really prefer lower case, it is much clearer, so we will spend the time to correct these when we can.
For the uploader, no input is needed, we are just letting you know so that you are not confused by seeing the occasional upper case colours in these registrations. The photos will be uploaded with upper case letters by the system and that cannot be helped. We will change them to lower case for you periodically. Uploaders need not worry that their chance of having a photo accepted will be damaged becasue the case is different to the photographs in the database. The newest photographs will inevitably be shown with upper case colours for a while, but we will change them as and when we can.