OpenCV Python save jpg specifying quality; gives SystemError

edit

>>> import cv2
>>> a = cv2.imread(r"DMap.jpg")
>>> a.shape
(1080, 1920, 3)
>>> cv2.imwrite('img_CV2_90.jpg', a, [cv2.IMWRITE_JPEG_QUALITY, 90])
Traceback (most recent call last):
  File "<input>", line 1, in <module>
SystemError: error return without exception set

I just installed the newest OpenCV 2.4 on windows 7 (32bit)/ Python 2.7.3, but I still get the same error I got using the beta version.

Also get this error with 2.4.1. Any ideas ? Using tuple instead of list, or adding a trailing 0 to the sequence does not help - same error.

Thanks - Sebastian Haase

PS: I asked this on http://stackoverflow.com/questions/10410521 - not resolving the issue.