"assertion failed (sha1_checksum != NULL)" in wc_db_pristine.c when updating a working copy upgraded from 1.6 to 1.7

Hi,

I get the following error when trying to update an existing working copy which was upgraded from 1.6. Is there any way to fix this locally without checking out a new working copy? I have a number of changes in the working copy, so I would rather continue using this checkout instead of creating a new one...

This happens with both commandline version of svn as well as latest TortoiseSVN, both report 1.7.0 as version number.

Commandline:

C:\data\trunk\jloadtrace>svn up
Updating '.':
svn: E235000: In file '..\..\..\subversion\libsvn_wc\wc_db_pristine.c' line 228: assertion failed (sha1_checksum != NULL
)

This application has requested the Runtime to terminate it in an unusual way.
Please contact the application's support team for more information.

C:\data\trunk>svn --version
svn, version 1.7.0-SlikSvn-1.7.0-X64 (SlikSvn/1.7.0) X64
   compiled Oct 10 2011, 17:03:32

Copyright (C) 2011 The Apache Software Foundation.
This software consists of contributions made by many people; see the NOTICE
file for more information.
Subversion is open source software, see http://subversion.apache.org/

The following repository access (RA) modules are available:

* ra_neon : Module for accessing a repository via WebDAV protocol using Neon.
  - handles 'http' scheme
  - handles 'https' scheme
* ra_svn : Module for accessing a repository using the svn network protocol.
  - with Cyrus SASL authentication
  - handles 'svn' scheme
* ra_local : Module for accessing a repository on local disk.
  - handles 'file' scheme
* ra_serf : Module for accessing a repository via WebDAV protocol using serf.
  - handles 'http' scheme
  - handles 'https' scheme

Tortoise:

---------------------------
Subversion Exception!
---------------------------
Subversion encountered a serious problem.
Please take the time to report this on the Subversion mailing list
(users_at_subversion.apache.org)
with as much information as possible about what
you were trying to do.
But please first search the mailing list archives for the error message
to avoid reporting the same problem repeatedly.
You can find the mailing list archives at
http://subversion.apache.org/mailing-lists.html

Subversion reported the following
(you can copy the content of this dialog
to the clipboard using Ctrl-C):

In file
'D:\Development\SVN\Releases\TortoiseSVN-1.7.0\ext\subversion\subversion\libsvn_wc\wc_db_pristine.c'
line 228: assertion failed (sha1_checksum != NULL)
---------------------------
OK
---------------------------

Dominik Stadler, Team Lead, R&D dynaTrace<http://www.dynatrace.com/>, dominik.stadler@dynatrace.com<mailto:dominik.stadler@dynatrace.com> Skype: stadler.dominik
www.dynatrace.com<http://www.dynatrace.com/> | blog.dynatrace.com<http://blog.dynatrace.com/> | ajax.dynatrace.com<http://blog.dynatrace.com/>

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