UPDATE
We found an much easier way to change the letter "N" indicating NEW
PAGES for an UPLOADABLE icon.
See the result **LIVE** on the page
http://de.wikipedia.org/wiki/Spezial:Recentchanges
The whole patch:
see
http://de.wikipedia.org/wiki/MediaWiki:newpageletter
<img src=/upload/X/YY/Neu.png>
* Replace "/upload/X/YY/Neu.png" with the relative URL on your wiki
* The URL is shown on the [[Image:Neu.png]] page after you uploaded it
to your wiki.
The uploaded image file page should be locked against unintended and
unwanted changes.
Tom
Berlin