The file applet/pilot.c contains a non-ascii character that causes many
warnings from xgettext when I update the sv.po (which is in UTF-8) with
"intltool-update sv":

xgettext: warning: The following msgid contains non-ASCII characters.
                   This will cause problems to translators who use a
character encoding
                   different from yours. Consider using a pure ASCII msgid
instead.
                   Copyright © 2000-2003 Free Software Foundation, Inc.
xgettext: invalid multibyte sequence
xgettext: invalid multibyte sequence
xgettext: invalid multibyte sequence
xgettext: invalid multibyte sequence


Also, the character (©) will not be displayed in the msgid in the po file,
it will simply be an extra space. Thus, this message cannot be translated
correctly as it is, and causes the above warnings with gettext 0.11 and
newer, and possibly also other gettexts.

As for possible solutions, either:

1) go back to using (C) in the msgid, or
2) un-mark this message for translation (if you are sure it doesn't
need localization).

Perhaps 2) is the best alternative. I don't know why this message would
need localization as it is written now.