Hi
I see from URL:http://www.debian.org/international/l10n/po/nb_NO and URL:http://www.debian.org/international/l10n/po/nn_NO that sysstat is one of the few packages using nb_NO and nn_NO as the langauge code for Norwegian Bokmål and Nynorsk.
I'm part of the Norwegian translation team, and we have agreed to name the .po files nb.po and nn.po instead of nb_NO.po and nn_NO.po. Would it be possible for you to change the name of the norwegian .po files in sysstat to nb.po and nn.po?
Cc to the norwegian translations mailing list.