Client connection limit?

[Luveno]

All:

Forgive me - I thought I saw this buried in a FAQ somewhere but I can't seem to find it again:

Is there a limit on how many clients can connect from a single public IP? I ask because tonight my wife, two kids, and I tried to play and only three of us could ever get on at one time (the other would get the "disconnected" message when trying to enter world).

The issue was not specific to an account or computer. Can someone confirm the limit? Is there a way to get it expanded to 4 so my whole family can play?

Thanks in advance.