How to register your nick and connect to one/several server(s) on mIRCI suggest you to read through the
Mirc For Everyone. guide first.
First of all you need to register your nick on the d2jsp server.
Type:
Quote
/ns register password email
Note that the email has to be valid one.After that you'll get an email with an
authentication code from d2jsp.
Now type:
Quote
/msg NickServ AUTH number from your email
(example: /msg NickServ AUTH 00000000)
After this, go to
Options 
Perform and mark the box
Enable perform on connect and add the following:
Quote
timer 1 2 nick (your nick)
timer 1 5 msg nickserv identify (your pw)
Now press "
Alt" + "
R" on your keyboard and this window will pop up:
Now add this text (three servers in this example):
Quote
on *:start:{
server irc.d2jsp.org -i (your nick) -j #d2jsp,#(channel 1),#(channel 2),#etc
server -m (other IRC server) -i (your nick) -j #(channel 1),#(channel 2),#etc
server -m (other IRC server) -i (your nick) -j #(channel 1),#(channel 2),#etc
}
If you only want to connect to one server, erase the two lines starting with "server -m", if you want to connect to two servers erase one of the lines and if you want to connect to four or more, just copy and past more lines.Example with two servers:
All you have to do now is click "
OK" and restart mIRC and you're done.