Removed the $userpage parameter from Namespace_Default::error_404(). It screwed up a couple plugins. (Thanks Mazza for discovering the issue)
tinyMCE.addI18n('en.paste_dlg',{
text_title:"Use CTRL+V on your keyboard to paste the text into the window.",
text_linebreaks:"Keep linebreaks",
word_title:"Use CTRL+V on your keyboard to paste the text into the window."
});