In the following save game http://dl.dropbox.com/u/5057853/pb_same_tile/on%20ennemy.EleSav a troll moved onto the same tile than my sovereign. It didn't engage combat (which is nice since I will surely have lots the combat). But I haven't the opportunuity to engage combat with this troll. It seems that in ordre to engage combat you need to move into the tile where the ennemy is.
