Interior object - item collision

I am working on creating a class similiar to item, but with some key behavior differences. One of these differences deals with how I handle the velocity of each object. I am, however having a problem with some collision detection between my new class and an interior object created with a diff file. When I create one of these itemlike objects on top of the interior object and set the velocity, I found that it very frequently collides with what appears to be nothing on a flat surface and bounces back. Upon further research I found that this collision behavior occurs in specific places. I iterated through the debug renderer to the view that displays the polygons and normals of the interior objects and found that these collisions occur at the seams of polygons. The surfaces are completely flat, with no spaces between polygons. The only thing that seems to be specific to these areas are that the polygon on which the item is traveling ends and a new one begins. I ran the debugger and found in the updatePosition() function that the item is colliding with a normal pointing in the opposite direction. Does anyone know why this happens? There is absolutely nothing visible in the object's path that it is hitting. The player can run over these areas with no weird collisions. If I place the itemlike object on a different interior object that has no seams, the strange collisions do not occur.