Terrain"skybox"

When you fly a vehicle out of the "mission area" the game engine seems to "rewrap" the terrain and you can fly away for what seems like forever. Problem is, as it generates this "terrain wrap" it wraps all the terrain landforms and "lakes" you had in the mission area into this so you see these landforms over and over (without the entities such as buildings). For example if you made a tall plateau with a lake at the top in your mission area, it would appear over and over again as the terrain wraps when you leave this mission area.

So, when I'm flying my F-4 Phantom around skirting the edges of the mission area waiting to drop some napalm and I decide to foray out into the "wrap" area I don't see my customized "plateau with lake at top" mirrored all over the place. (How's that for a run-on sentence?)
I basically would just want the "non customized" terrain to wrap itself without any of the custom height changes I made to the mission area present.

That's why I labeled this post "terrain skybox" because I was wondering if you could get the wrapping properties to select a smaller sample of the general terrain to do the "wrapping" with. I know something like this would be possible with extensive modification, but like everyone else I would like the easiest possible solution :)

Any ideas on how to accomplish this would be greatly appreciated!!!

Scott Schaefer