Releasing a MultiModuleMavenProject on a jenkins-slave via m2release-plugin always fails:

[INFO] Checking in modified POMs...
.
svn: E155004: Working copy 'C:\JenkinsDATA\workspace\MavenDemoDeploy' locked; try performing 'cleanup'

If I make the initial checkout and maven release build on command-line of the slave-machine everything works fine. If I make the release build on jenkins-slave for a single maven module everything works fine. If I make the release build for the multi maven module on the master everything works fine.

I configured the release-plugin to use the svnkit, so it is the same client as jenkins use to checkout. I also configured preparationGoals to make a 'svn cleanup' (the cleanup works) without any success.