Undernet's AUP states:
On Mon. Aug 11, 2008, xplora states:Limit connections to 3 per User or IP for Primary Access providers. This will be strictly enforced at 5 connections. Exceptions for *primary* internet access (netcafes, college dorms and a few others) can be requested by contacting firstname.lastname@example.org;
Looks like http://www.undernet.org/aup.php (Undernet's posted AUP) needs to be email@example.com isn't really the place to ask, you have to organise it with a server admin, you can find the admin contact details of the server you would like the extra connections on with /motd or /admin while connected to the server you would like the connections on.
I post this here, assuming this is the responsibility of the Undernet User Committee and in the hopes that representatives of that committee read this section of the forum.