No way to do it through the UI, but it is very easily scripted, and you can even specify channels to start out with (or you can have those in the perform)
Code:
on *:START:{
  server irc.network1.net
  server -m irc.net-work2.co.uk
}

Just put that into a blank Remotes file (hit Alt+R, and then file -> New if there is something there. To specify a channel, just say -j #channel1,#channel2 after the server name.

/help /server for more detailed commands