Cannot open the message catalog "man"

sunkvip

每次运行 man somecommand，就会提示:

Cannot open the message catalog "man" for locale "zh_CN.utf8"
(NLSPATH="<none>")

No manual entry for somecommand

#locale
LANG=zh_CN.utf8
LC_CTYPE=zh_CN.utf8
LC_NUMERIC=POSIX
LC_TIME=POSIX
LC_COLLATE="zh_CN.utf8"
LC_MONETARY="zh_CN.utf8"
LC_MESSAGES=POSIX
LC_PAPER="zh_CN.utf8"
LC_NAME="zh_CN.utf8"
LC_ADDRESS="zh_CN.utf8"
LC_TELEPHONE="zh_CN.utf8"
LC_MEASUREMENT="zh_CN.utf8"
LC_IDENTIFICATION="zh_CN.utf8"
LC_ALL=

man的USE:
sys-apps/man-1.6c  USE="nls"

#echo NLSPATH 输出为空

请教解决方案，谢谢！