Code:
on ^*:join:#channel: {
.msg $nick Hello $nick $+ , Welcome to #channel . May we have your age Please ?
}

Change #channel to your channel name, and place it in remote in your mirc. ALT + R will open up the script editor/remote.

you can also use:
Code:
on ^*:join:#channel: {
if ($nick == moo) .msg moo Hello $nick $+ , you are moo.
elseif ($nick == foo) .msg $nick hello $nick $+ , you aren't moo.
elseif ($nick == baa) .msg $nick hello $nick $+ , you aren't foo or moo.
else {
 .msg $nick Hello $nick $+ , Welcome to #channel . May we have your age Please ?
}
}


the . hide the message from you, not fun watch all messages sent if you are on active channel.

if ($me != tired) { return } | else { echo -a Get a pot of coffee now $+($me,.) }