Ummm I don't know if I should be reply here but localhost generally resolves to 127.0.0.1 which is your OWN computer so that could be a problem! See if there is anywhere you can change localhost to goth.net. If not....
...and if you are running XP or less, go to Start, Run, then type
telnet goth.net 143
Then it will come up with a black box with some funny words.
a01 login (your username) (your password)
(if you stuff up, you can't press backspace to fix the typo, you will need to try again on a new line)
...and press enter. If it works and says you are logged in then there is a problem with your email client which means you will need to provide more information such as which email client you are using e.g. Outlook or whatever.
To get out of the telnet box just type
However if you would rather wait for an official response feel free to completely ignore this.
Also to the fuhrers of goth.net, apologies if I shouldn't be replying to this...