Odd unpack failed error (Missing unknown 00000000000000....)

[GoogleCodeExporter]

Affected Version: 2.1.1

What steps will reproduce the problem?
1. I have an existing repo that I moved into $site/git
2. I added the project, etc.
3. I did a git clone, and created a test commit.
4. I did "git push origin HEAD:refs/for/mybranch"

What is the expected output? What do you see instead?
I expected it to commit, but I got this:
Counting objects: 5, done.
Delta compression using 2 threads.
Compressing objects: 100% (3/3), done.
Writing objects: 100% (3/3), 364 bytes, done.
Total 3 (delta 2), reused 0 (delta 0)
error: unpack failed: error Missing unknown 
0000000000000000000000000000000000000000
To ssh://meta:29418/vivisimo/7.5
 ! [remote rejected] HEAD -> refs/for/mybranch (n/a (unpacker error))
error: failed to push some refs to 'ssh://meta:29418/vivisimo/mybranch'

Please provide any additional information below.

I can't provide my repo to anyone, since it is private.  However, I'm willing 
to do whatever experiments you might want.

Original issue reported on code.google.com by docw...@gmail.com on 18 Feb 2010 at 7:52

[GoogleCodeExporter]

What was the client version?

Gerrit shouldn't have tried to look for 0x40 unless the client
said that was the object to push into refs/for/mybranch.  But
that makes no sense, unless the Git client is busted and sent
the wrong command sequence.

Can you reproduce this at will?  If so I can try to come up with
some sort of extra debugging we can try here.  Right now I'm
just struggling to find where that error "unpack failed" came
out of.  The string doesn't appear anywhere in JGit or within
Gerrit Code Review...

Original comment by sop@google.com on 22 Feb 2010 at 3:57

• Changed state: AwaitingInformation

[GoogleCodeExporter]

I can create this at will.  Feel free to send me debugging war files and 
instructions on 
use.

You can contact me out-of-band of this bug at http://docwhat.org/  Either using 
the 
alter egos (for IM, etc.) or you can email me at docwhat @ the company that 
begins with 
'g' ...and ends with oogle.  Don't forget the '.com'.

Ciao!

Original comment by docw...@gmail.com on 22 Feb 2010 at 4:14

[GoogleCodeExporter]

I'll get you the client version tomorrow, when I get to work.

Original comment by docw...@gmail.com on 22 Feb 2010 at 4:15

[GoogleCodeExporter]

git version 1.6.2.1

Original comment by docw...@gmail.com on 22 Feb 2010 at 2:47

[GoogleCodeExporter]

Was the client repository a shallow clone by any chance?

Original comment by sop@google.com on 24 Feb 2010 at 4:10

[GoogleCodeExporter]

I used gerrit's ssh/git repo server to do the clone.

Original comment by docw...@gmail.com on 24 Feb 2010 at 4:36