After a few attempts, I've seen that is impossible to import a custom xar containing pages with accents. I've followed the procedure describe here and nothing works. It's not because of the program of compressing I use cause I've met no problems when my custom xar didn't caontain pages with accents.
The error Tomcat is :
The problem is there ONLY with custom xar. Using the API Export/Import, so in order to do a whole backup, the problem doesn't appear. Once again, I've followed the official procedure in order to create my custom xar. Last thing, I'm using Windows environment.