"unkown type" problem with EXIF.py from gene cash

[leo]

hi there

i'm using gene cash's EXIF.py module to find out the shoting time of an jpeg
image.

this module works usually like a beauty, but some images raise an exception:

Traceback (most recent call last):
  File "/Users/Shared/bin/exiftool.py", line 148, in ?
    tags=EXIF.process_file(f)
  File "/Users/Shared/lib/python/EXIF.py", line 1032, in process_file
    hdr.decode_maker_note()
  File "/Users/Shared/lib/python/EXIF.py", line 925, in decode_maker_note
    dict=MAKERNOTE_CANON_TAGS)
  File "/Users/Shared/lib/python/EXIF.py", line 762, in dump_IFD
    raise ValueError, \
ValueError: unknown type 768 in tag 0x0100

this means that for thse images no exif data at all is usable, even though
only on tag couldn't be read. :-(

all this trouble causing images are rotated by an other appliaction (iPhoto
on OS X).

does anybody knows a workaround with this module or even a solution with
another/improved exif reader?

thanks a lot, leo