Join Error

Hello.
When someone join one of our servers, we can't connect to this server about 5 seconds.
When I try to connect so the server I get this error.
http://www.imagebanana.com/view/f7dhlmvy/fehler.png

Could someone help me?
I use Spigot 848 and Bungee 405 (latest versions)

I think I get this error since 1.5.2 but I'm not sure :/

Sorry for my bad englisch .

Thanks oOFlaashOo