Wrong language file

[Boyquotes]

Hello,

I try to have a french ispcp panel, but the fr_FR.po file don't work, and any other language ( http://isp-control.net/ispcp/wiki/translations )

Display error in red:
Uploaded file is not a valid language file
or
Uploaded file does not contain the language information

I don't understand why the internalisation don't work, in another installation the same file work fine...

Have a nice day.
Nicolas.