Possible Boat Bug?

[Steelrain60]

I think I might have encountered a bug in RS.

I'm playing Jumbo in "Kuching", and I loaded an empty motorboat with an engineer platoon in order to move the boat out of the way of the Japanese advance. When I loaded the troops, the motorboat icon suddenly turned into a rubber raft. I hit the "reachable hexes button" next turn and it showed four hexes (it costs 25 for a motorboat to move one hex), but the unit proceeded to act like a raft, costing 50 AP to move one hex of shallow water.

Weird, huh? Anybody seen anything else like this?