Local file issue

// App controller call
Configure::write('Config.language', 'swe');

// File \app\Locale\eng\LC_MESSAGES\default.po
msgid "WeddingLife"
msgstr ""

// File \app\Locale\swe\LC_MESSAGES\default.po
msgid "WeddingLife"
msgstr "Bröllogram"

// All the string WeddingLife is written everywhere like this
echo __("WeddingLife");

But this word is not changing. The sentences with this word "WeddingLife" is also not converting to swe(I have given other tags also.) Can anyone help? I am searching and reading for last 3 hours but not able to find a solution.

Thanks in advance.