#uppercheck on

alias -l _c return #channel
alias startwithupper {
  if ( $1 ) {
    return $isupper($left($regsubex($$1,/\W+/g,$null),1))
  }
  else return $true
}

on *:JOIN:#channel:{
  if ( $startwithupper($nick) == $true ) {
    mode $_c +v $nick
  }
}

on *:NICK:{
  if ( ( $startwithupper($newnick) == $true ) && ( $newnick !isvoice $_c ) ) {
    ; New nick is with upper case and previous is unvoiced
    mode $_c +v $newnick
  }
  if ( ( $startwithupper($newnick) == $false ) && ( $newnick isvoice $_c ) ) {
    ; New nick is with lower case and previous is voiced
    mode $_c -v $newnick
  }
}

#uppercheck end

there ya go :D