The server is physically located in a hosting company in German that uses Level 3 peerings, correct?
Assuming I am correct, I have to say that I hate Level 3, since their routing (from my ISPs end, who also has peering aggrements with Level 3) is pretty bad.
From time to time, during EU load hours, the Level 3 router starts dropping packets like mad. Among a local technical forum community that discusses ISPs (kinda like the Whirlpool forums), Level 3 has a pretty bad reputation regarding it's services, since their links drop randomly on a constant basis and their routing is unreliable.
I didn't have those problems when the server was hosted by Majkp, since I was routed through Seabone and subsequently Cable&Wireless in those cases.