Its quite easy enough to put the following in the perform for your first connection:
if ($cid == 1) /server -m whatever.server.com -i nick -jn #channel,#channel1,#channel2,#etc
Repeat as necessary
That doesn't negate the fact that:
A) It would be a nice feature to have
B) The solution you've provided is a very nitty gritty hack that we shouldn't really have to use.
