The user from "The user xwiki:XWiki.X? successfully joined wiki Y" is not well displayed

Steps to reproduce:

1. Create a (sub)wiki open for users (for both local and global users)
2. Log-in in that (sub)wiki with a global user
3. Click on "Join this wiki" option from (sub)wiki Main page
4. You see that the user's name is not well displayed and when you press click on its name, you see an error message on your screen ("An error occured, please refresh the page) and try again

Tested on IE10.