Segfault on merge with 1.6.2.1

Greetings.

I'm trying to figure out what's going on with a merge I'm trying to do. As  
far as I know, it's a fairly standard situation, just merging two  
branches. But I get a segfault each time. This occurs with 1.5.6.5 and  
1.6.2.1. The earlier version is on a Debian Etch box with  
backports.debian.org. The latter is Debian Sid. I also tried on a Windows  
box with MSysGit 1.6.2.1-preview20090322.exe.

The 1.6.2.1 version just segfaults, but 1.5.6.5 says:

/usr/bin/git-merge: line 438: 32335 Segmentation fault       
git-merge-$strategy $common -- "$head_arg" "$@"
Merge with strategy recursive failed.

In all cases, .git/index.lock is left behind.

I'm using the default configuration, with only a few basic options in my  
person .gitconfig.

Unfortunately, I cannot post the archive, but I can tar the archive and  
share that with individuals, if need be.

The problems started with a weird merge by another developer a while ago  
that somehow reapplied earlier commits. It looked like he had done some  
commits that wiped some earlier commits but then a commit or two latter  
the old commits were added back. When I tried to merge the resulting  
master into my working branch it segfaulted. I didn't have time (or the  
immediate need) to look into it then and it's been forgotten until now  
(when, of course, it needs to be done in the next few days :( ).

I have run git gc and also pruned a couple of minor dangling objects.  
Running git fsck --full reveals no problems. The largest file is about  
6MiB.

I've asked on #git, and drizzd there suggested I try here. At this point  
I'm completely at a loss.

Any help would be greatly appreciated.

Thanks,
Michael

-- 
Michael D Johnson   [off-list ref]    
redbeardcreator.deviantart.com

"Marketing research...[has] shown that energy weapons that make sounds sell
  better..." - Kevin Siembieda (Rifts Game Master Guide, pg 111)