It seems that textures are getting flipped (or not getting flipped) like they did in previous versions.
Either way, I solved it by creating a custom block renderer and drawing the faces individually and then flipping the textures for the north and east faces.
here is a bit of the code I used:
@Override
public boolean renderWorldBlock(IBlockAccess world, int x, int y, int z,Block block, int modelId, RenderBlocks renderer) {
block.setBlockBounds(0, 0, 0, 1, 1, 1);
renderer.setRenderBoundsFromBlock(block);
for (int d = 0; d<6;d++) {
ForgeDirection dir1 = ForgeDirection.getOrientation(d);
if (block.shouldSideBeRendered(world, x, y, z, dir1.getOpposite().ordinal())) {
if (dir1==ForgeDirection.NORTH || dir1==ForgeDirection.EAST) {
renderer.flipTexture=true;
}
switch(d) {
case 0:renderer.renderFaceYNeg(block, x, y, z, block.getIcon(world, x, y, z, d));break;
case 1:renderer.renderFaceYPos(block, x, y, z, block.getIcon(world, x, y, z, d));break;
case 2:renderer.renderFaceZNeg(block, x, y, z, block.getIcon(world, x, y, z, d));break;
case 3:renderer.renderFaceZPos(block, x, y, z, block.getIcon(world, x, y, z, d));break;
case 4:renderer.renderFaceXNeg(block, x, y, z, block.getIcon(world, x, y, z, d));break;
case 5:renderer.renderFaceXPos(block, x, y, z, block.getIcon(world, x, y, z, d));break;
}
renderer.flipTexture=false;
}
}
renderer.clearOverrideBlockTexture();
block.setBlockBounds(0f, 0f, 0f, 1f, 1f, 1f);
renderer.setRenderBoundsFromBlock(block);
}