Hi Marco António,
while the issue you comment (MDL-21432) is important (it's the complete backup & restore implementation) I wouldn't recommend to vote on it for particular issues like the one commented in this discussion. Instead, it's always better to create a new issue in the Tracker providing all the information available about the problem, how to reproduce it and so on. That's the way for problems like this.
Of course, feel free to vote the issue above, as far as it's really important, but let me say that, being the assignee for that issue since 1 year ago, I already know it's (very) important. It has been my main focus since then, lol, so some dozens (or hundreds) of votes won't help, lol (note this is a side-joking comment).
Ciao