navigation in d kepubs, FW 3.1.1

I have the above on a Mini, which is not supposed to run it - this aside, the firmware works perfectly well, the only problem being that I can no longer navigate to "previous position" in sideloaded kepubs (e.g. when jumping to a footnote): is this a known bug? I use joel's plugin. The books in question were already there before I sideloaded FW 3.1.1 (I reported this here, but I am repeating myself as I think it went unnoticed :D).

Happy New Year!