Naval/Land Targeting issue

It seems that the combination of NavalTargeting=7 and LandTargeting=2 causes strange inconsistencies with the targeting of units.

In a test I just ran, a ship gladly auto-acquired other _naval targets_ using its primary anti-ship weapon, which has a range of 13 cells.

However, when I gave it an attack-move order to a piece of land (being a hover-craft) where a few enemy tanks were, it did not acquire the tanks. It didn't acquire them in guard-mode or when otherwise idle, also. It only attacked these land units when they attacked it. (the secondary being an anti-ground weapon with 9 cells range)

##### STEPS TO REPRODUCE #####
This should be able replicate the effect.
1: Make a naval unit with NavalTargeting=7 and LandTargeting=2
2: Send to a location where it can engage enemy ships. It should automatically target them.
3: Send to a location where it can engage enemy ground targets. It should not target them unless fired upon.

##### ADDITIONAL INFORMATION #####
This is an odd bug, and I filed it as "sometimes" as I have fuzzy memories of this not always happening with the unit. I've attached the code for the unit in question.