/brb /amsg Be Right Back | /chanserv deop | /nick yournick|afK
/bk /amsg Back | /nick yournick | /nickserv identify PASS /chanserv op 

Intresting, could be this :O

Alias brb {
amsg Be Right Back
tnick $me $+ |away
awat Brb command used
}
alias Back {
amsg Back, i was gone for $awaytime
tnick $remove($me,|away)
away
}

No need for deops, its kinda pointless, and the one i just did works in remotes and alias, just remove the aliases part if you want it to work in aliases :P