Specifying bounds for Tileset will generate at incorrect latitude

[BirdSamuel]

After generating an OpenStreetMap Tileset with bounds exactly around the Noblis office in Virginia: [-77.21917, 38.85804, -77.21295, 38.86337], we found that the caching of tiles and bounds ends up a lot further South (near Peru). There is sometimes a big white streak below the cached area.

To fix this, we negated the Y values of the bounds, resulting in [-77.21917, -38.86337, -77.21295, -38.85804]. This fixed the problem, but is wrong in the end. We tried modifying the projection + grid (from EPSG:4326 to EPSG:900913 and vise-versa, also to EPSG:3857). Modifying the origin of the grid from 'sw' to 'nw' (GLOBAL_MERCATOR, GLOBAL_WEBMERCATOR respectively) changed where it placed the imagery (placed Peru's tiles onto Virginia) but not what tiles were being cached.