svn mv and svn cp fails in 1.8.8 and 1.8.9

Hi,

when I try to cp or mv a directory within a repository, I get (after
several seconds of waiting with no cpu/disk activity) the following
error.

rj_at_sol$ svn cp .test_equ_simple/ /opt/PetaMem/PMLS/active/data/lexica/c/e/s/
svn: E200033: Another process is blocking the working copy database,
or the underlying filesystem does not support file locking; if the
working copy is on a network filesystem, make sure file locking has
been enabled on the file server
svn: E200033: sqlite[S5]: database is locked
svn: E200033: Additional errors:
svn: E200033: sqlite[S5]: database is locked

the sandbox is then in a "L" state and has to be "svn cleanup"ed

a simple cp, with subsequent svn add for the target (instead of svn
cp) and eventually svn del in the source (instead of svn mv) works,
but this workaround seems like subversion 1.2 - or worse.

for reference
-----------------------------------------------------------
# svn --version
svn, version 1.8.9 (r1591380)
   compiled Jun 13 2014, 14:35:55 on x86_64-pc-linux-gnu

Copyright (C) 2014 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_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.
  - using serf 1.3.4
  - handles 'http' scheme
  - handles 'https' scheme
-----------------------------------------------------------

kind regards,

-- 
     Dipl.-Inf. Univ. Richard C. Jelinek
PetaMem GmbH - www.petamem.com          Geschäftsführer: Richard Jelinek
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