Description of Problem:
When there are multiple nested theme directories, the tree that is built is
corrupted; some themes appear at the top level of the tree instead of in
their subtrees, and some disappear altogether.

Version-Release number of selected component (if applicable):
2.8.1-3 has the problem, and it has existed for some time (pre-Roswell), I
finally got around to reporting it :o)

Additional Information:
I have a band-aid "fix" which I attach, which disables the use of the
"sibling" tracking while building the tree; it works then.  I think the
code is trying to be too clever; as the tree gets sorted anyway there is no
need to keep track of the position entries are being inserted into the
subtrees.  Anyway, it works correctly with this patch.  I will attach it in
a moment, with the modified spec file.