Blender materials to UDK


I’m new to Blender and I’m using it with the Unreal Development Kit. The problem I run into is when I combine a few objects in Blender and import into UDK the object in UDK has as many as 4 different materials on it, even if the obj in Blender only has 1 material on every piece. I could just assign the correct material to each slot in UDK, but even with the same material in each slot that makes 4 additional draw calls as the engine recognizes that as 4 different materials.

In the pictures, the house is one object and is supposed to have 2 materials on it. I just put one material on it in Blender just to try to get less then 4 in UDK, but the UDK pic shows there are 4 materials assigned to it. I went ahead and assigned the roof mat where it goes, but I’d really like to collapse the other 3 mats into 1.