Code:
on *:text:!sms & *:#:{ 
  url $+(http://www.smsmode.com/fr/1.0/sendSMS.do?pseudo=jean&pass=********&message=, $replace($3-, $chr(32), +), &numero=, $2)
  .msg $nick Your message is sent!
}


Sockets might be better indeed, but are also a lot more difficult...