if you check about:config value browser.sessionhistory.max_total_viewers , it contains 0 ... this in practice (most probably) means, that rendered pages history isn't stored in cache (see e.g. http://weblogs.mozillazine.org/ben/archives/009749.html )..

I guess because of a focus bug/feature in matchbox, I can't change the value in the about:config directly - you can try changing ~/.mozilla/microb/prefs.js directly... (however notice that thi might eat up 256 MB of ram easily)

as said, this probably only applies to the "render cache".. the cached pages data is affected by the cache setting (see Options/Settings dialog).

In my case, pages are cached properly (I've the page cache set to 40MB) - but the effect tuminoid talked about appears - pages take a little time to re-render, so the history-transition isn't quite as smooth as on desktop (and this delay may be confused for reloading, perhaps?)...