cannot rename versioned package

Hello,

I have a package de.unituebingen.sfs.macke.trees, containing three
classes. I want to rename it to de.unituebingen.sfs.macke.sentences.
The refactoring works fine, but committing does not work, it gives the
error:
commit -m "introducing sentences instead of trees" -N
/home/hendrik/workspace/MSO/de/unituebingen/sfb/macke
/home/hendrik/workspace/MSO/de/unituebingen/sfb/macke/sentences
/home/hendrik/workspace/MSO/de/unituebingen/sfb/macke/trees
/home/hendrik/workspace/MSO/de/unituebingen/sfb/macke/trees/BranchingTree.java
/home/hendrik/workspace/MSO/de/unituebingen/sfb/macke/trees/LeafTree.java
/home/hendrik/workspace/MSO/de/unituebingen/sfb/macke/trees/Tree.java
     Trying to use an unsupported feature
svn: Cannot non-recursively commit a directory deletion

What is going wrong here?

TIA, H.

-- 
Hendrik Maryns
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