corrupt repos does not return error with `git fsck`

Hi,

Clone the repos https://github.com/fmitha/SICL.

Then

     git show 280c12ab49223c64c6f914944287a7d049cf4dd0

gives

     fatal: bad object 280c12ab49223c64c6f914944287a7d049cf4dd0

But

     git fsck

gives

     Checking object directories: 100% (256/256), done.
     Checking objects: 100% (49356/49356), done.

So `git fsck` does not return an error, though the repos is corrupt. This 
may be of interest to the developers.

Please CC me on any reply, I'm not subscribed to the list. Thanks.

                                             Regards, Faheem Mitha