Notify #racket channel option causes error in irc-bot

[SimonLSchlee]

How to reproduce

Submit a paste with the "Alert #racket; your nick:" option enabled and your nickname in the input box.

Error message

`tcp-write: error writing
system error: Broken pipe; errno=32

for-loop at:
line 50, column 2, in file /home/pasterack/pasterack/irc-bot.rkt
irc-paste at:
line 49, column 0, in file /home/pasterack/pasterack/irc-bot.rkt
process-paste23 at:
line 466, column 0, in file /home/pasterack/pasterack/pasterack.rkt
at:
line 342, column 33, in file /home/pasterack/racket68/collects/racket/contract/private/arrow-higher-order.rkt
at:
line 342, column 33, in file /home/pasterack/racket68/collects/racket/contract/private/arrow-higher-order.rkt`