Not sure how best to contact those who need to be notified. I'm hoping this forum will work. The refbase web site (http://www.refbase.net) appears to be having issues. It's been returning Internal Server Errors since at least yesterday (11/25/2012).
I sent an email to Matthias, but I am sure they know about before.
Website is back again
many thanks for notifying us about the website server issue. I've also noticed this yesterday and contacted my ISP about it. As Knut remarked, the issue appears to be fixed now. Interestingly, only www.refbase.net (aka wiki.refbase.net) seemed to be affected by this server issue, while demo.refbase.net (and other services on that server) where still up and running.
W.r.t. the website, I'm aware that it also needs some content maintenance (quite a few links need to be updated, etc.). I'll try to address this soon.
Best regards, Matthias