I've opened up SCM-406 and created this issue so to track this problem in the Release Plugin project.
release:prepare fails due to svn "file exists" complaint
Add a mojo parameter for using the new remote tagging for svn scm provider (to prevent issue with svn > 1.5.0)
scm tag does not work with Subversion 1.5.1
workaround will be implemented by MRELEASE-427.
Workaround implemented in MRELEASE-427.
To test it you have the apache snapshots repo : https://repository.apache.org/content/groups/snapshots
And configuring release mojo as this :