Merge gives E160013 Error after upgrade to svn-1.7.10

[Joakim Schramm]

Hi list,

my first post as I subscribed due to my problem, so please be gentle in 
case I don't get it right ;-)

After upgrading from svn-1.7.9 to 1.7.10 and doing a merge operation 
have done regularly during the last 2 years or so, I now get an E160013 
Error:

svn dev # svn merge ^/vendor/d7-core/drupal-7.x-dev_2013-Jun-06 
^/vendor/d7-core/current
svn: E160013: File not found: revision 4124, path 
'/vendor/d7-core/drupal-7.x-dev_2013-Jun-06'

The background is this: In my repo I run a vendor branch keeping track 
of Drupal as well as a collection of Drupal modules and themes. In the 
same repo I also vc a collection of web sites, which are all tracked 
against the vendor branches.

On Thursday evening I upgraded to 1.7.10, and on Friday I made my first 
vendor update with the new version, updating Drupal 7 code, using the 
svn_load_dirs script:

svn_load_dirs.pl -t drupal-7.x-dev_2013-June-21 -svn_username xxxx 
-svn_password yyyy svn://svn.xxxx.com/www/vendor/d7-core current 
/tmp/drupal-7.x-dev

and as from what I can judge nothing seems to be wrong with the output 
and the commits are done. I can post the output in case it's needed/wanted.

I then (try to) make the merge operation above in the web root of one 
site resulting in the error.

Subversion is running on a Gentoo Linux server using svnserve. I also 
work with this repo from a Windows workstation using TSVN and using the 
TSVN repo browser I can clearly see that the 'not found' file (which 
actually is a dir) is present.

'revision 4124' is the last revision in repo created by the load_dirs 
script.

Well, I don't know where to start looking as I can't really see anything 
is wrong, except for the error message, but hopefully someone else can 
or have an idea, or is this possibly a bug?

thanks,

Joakim