Matrix slice operations on images fail (Bug #1393)

Doing simple matrix slice operations on images makes subsequent OpenCV methods working on the same image fail, i.e.:

Extracting a single channel:

1import cv2
2image = cv2.imread('door.png')
3image = image[:,:,1]
4cv2.imshow(u'Image', image)
5cv2.waitKey()

OpenCV Error: Bad flag (parameter or structure field) (Unrecognized or unsupported array type) in cvGetMat, file /tmp/homebrew-opencv-2.3.1a-SZiB/OpenCV-2.3.1/modules/core/src/array.cpp, line 2482
Traceback (most recent call last):
  File "./bwe.py", line 8, in <module>
    cv2.imshow(u'Image', image)
cv2.error: /tmp/homebrew-opencv-2.3.1a-SZiB/OpenCV-2.3.1/modules/core/src/array.cpp:2482: error: (-206) Unrecognized or unsupported array type in function cvGetMat

Another example: Mirroring the image:

1import cv2
2image = cv2.imread('door.png')
3image = image[:,-1::-1,:]
4cv2.imshow(u'Image', image)
5cv2.waitKey()

OpenCV Error: Assertion failed (src.dims <= 2 && esz <= (size_t)32) in transpose, file /tmp/homebrew-opencv-2.3.1a-SZiB/OpenCV-2.3.1/modules/core/src/matrix.cpp, line 1680
terminate called throwing an exceptionAbort trap: 6

The funny thing is that inserting the following line of code after the matrix slice operation (line 3) will make both examples work as expected without errors:

image = image * 1

I'm using Mac OS X 10.7.1 with Xcode 4.1, Python 2.7.2 and OpenCV 2.3.1a; with Python and OpenCV installed using Homebrew.