But this strings is 61 characters accord to wc! If you really need it to be shorter, maybe this is OK:
msgid "Retry network autoconfiguration with a DHCP hostname" msgstr "Prøv auto-nettverksoppsett igjen med et DHCP-vertsnavn"
Indeed, the bug reporter probably used an outdated version of D-I. You're right about the length. It is OK already so this bug can be closed safely.