git-svn mergeinfo support performance problem

I've been testing git-svn v1.6.6-rc3's mergeinfo support on a large svn repository (60,000+ revisions, 20+ GiB) that uses a very branch-heavy integration model in which every change gets its own branch before being committed to trunk. As a result of the model, there are currently over 1000 lines in the svn:mergeinfo property on trunk. Unfortunately, with the current implementation, git svn fetch takes more than a minute per revision pouring through all of those merge tickets; obviously, this is too slow to be usable for my repository.

Are there any ideas on how git svn fetch can be sped up when facing hundreds of mergeinfo properties?  Alternatively, would it be possible to add an argument that would ignore the merge info?  Or, is there any maintenance I could perform on the svn repository that would help reduce the amount of work that git-svn must do?  In the meantime, I'll have to stick with git 1.6.5.*.

Regards, Andrew

P.S.  This is my first post to the list.  My apologies if this issue has already been discussed and I did not see it in the archives, or if I have missed a more formal mechanism for filing bug reports.