This one is 127 chars. I hope it still works - if not correct me. :)

#23456789012345678901234567890123456789012345678
$b=join'',@_={+pop};$a={map{$_[$_],$_[$_+1]}0..
@_-2};$_=join',',grep$b=~s/\Q$_//g,@_;s/(.)(?:,(
(??{"\Q$$a{$+}"})))+/$1..$+/g;$_
[download]

$§=lc(sub{}^" \6 \n");$§=~s/\(.*\)//;for(split ('',$§)){$/=$_;for(5..7){$/++}$:.=$/}print$:;1