I have updated the translation of Subscribe2 to norwegian using the plugin Codestyling Localization. Download here.
There are some strings however that are not dicovered. These are:
Every 5 Minutes
Every 10 Minutes
Every Half an Hour
The string "text" has a mis-spelled textdomain subsribe2 (without the c) and the string "Subscribe2 Widget" has no textdomain (or default).