Log potential error messages for later re-viewing

[tlue]

Hi
It is actually more of a wish than a bug:

When logging in an switching on my USB disk the backup kicks off automatically (which is great, thanks for that!). Now after a while I do get the message that not all files have been backed up (Ubuntu 1204 Gnome desktop). but when clicking on it, it just disappears (as all of them do) instead of showing me what the issue is.
When then going into Backup I can't find any where to click to show i.e. error of last run.
When running the backup now again from here manually I do get the window listing all information.

Would it be possible to store those messages from that window into a log file in case Backup (déjà-dup) runs from the scheduler and this window is not visible to the logged in user?

Thanks,
Thomas

lsb_release -d
Description: Ubuntu 12.04.3 LTS

dpkg-query -W deja-dup duplicity
deja-dup 22.0-0ubuntu4
duplicity 0.6.18-0ubuntu3.1