contrary to RFC1413, some IRC networks cannot handle special characters
in the ident response (e.g. '+' on freenode)

increase the length of sent response from 8 to 12 to make up for the
lost character range (of which many popular networks only use 10)

not even all freenode hosts have a reverse dns ending in .freenode.net,
some (quakenet..) often have none at all, so our heuristic is pretty
much useless