git-svnimport failed and now git-repack hates me

So I'm using git 1.4.1, and I have been experimenting with importing
the KDE sources from Subversion using git-svnimport.

First issue I ran into: On a machine with 4GB of RAM, when I tried to
do a full import, git-svnimport died after 309906 revisions, saying
that it couldn't fork.

Checking `top` and `ps` revealed that there were no git-svnimport
processes doing anything, but all of my 4G of RAM was still marked as
used by the kernel. I had to do sysctl -w vm.drop_caches=3 to get it
to free all the RAM that the svn import had used up.

Now, after that, I tried doing `git-repack -a` because I wanted to see
how small the packed archive would be (before trying to continue
importing the rest of the revisions. There are at least another 100k
revisions that I should be able to import, eventually.)

The repack finished after about nine hours, but when I try to do a
git-verify-pack on it, it dies with this error message:

error: Packfile
.git/objects/pack/pack-540263fe66ab9398cc796f000d52531a5c6f3df3.pack
SHA1 mismatch with itself

I get the same message from git-prune.

Any ideas?