Biber failes to validate

Question

I installed Biber 1.7 and biblatex 2.7a from the opensuse Publishing:/TeXLive/ repository. As the problem posted earlier - no bbl output is produced although biber pretends to do so - persists, I tried to validate biber using the test files:

adessec@ipek:~/Dokumente/Privat/EDV> biber --validate_control --convert_control test
INFO - This is Biber 1.7
INFO - Logfile is 'test.blg'
ERROR - 'test.bcf' failed to validate against schema '/tmp/par-adessec/cache-1810d1114b7baebb573cdb31a20722a23dce204b/inc/lib/Biber/bcf.rng'
INFO - ERRORS: 1

Here is biber output without any extra options (the final info that test.bbl was written is misleading):

adessec@ipek:~/Dokumente/Privat/EDV> biber test
INFO - This is Biber 1.7
INFO - Logfile is 'test.blg'
INFO - Reading 'test.bcf'
WARN - Warning: Found biblatex control file version 2.0, expected version 2.5
INFO - Found 1 citekeys in bib section 0
Use of uninitialized value $label in string eq at /tmp/par-adessec/cache-1810d1114b7baebb573cdb31a20722a23dce204b/inc/lib/Biber/SortLists.pm line 77.
Use of uninitialized value $label in string eq at /tmp/par-adessec/cache-1810d1114b7baebb573cdb31a20722a23dce204b/inc/lib/Biber/SortLists.pm line 77.
INFO - Processing section 0
INFO - Looking for bibtex format file 'test.bib' for section 0
INFO - Decoding LaTeX character macros into UTF-8
INFO - Found BibTeX data source 'test.bib'
WARN - Labelname candidate 'author' is not a name field - skipping
INFO - Overriding locale 'de_DE.UTF-8' default tailoring 'level = 4' with 'level = 2'
INFO - Overriding locale 'de_DE.UTF-8' default tailoring 'variable = shifted' with 'variable = non-ignorable'
INFO - Sorting 'entry' list 'MAIN' keys
INFO - No sort tailoring available for locale 'de_DE.UTF-8'
Use of uninitialized value $llabel in concatenation (.) or string at /tmp/par-adessec/cache-1810d1114b7baebb573cdb31a20722a23dce204b/inc/lib/Biber.pm line 1926.
Use of uninitialized value $llabel in concatenation (.) or string at /tmp/par-adessec/cache-1810d1114b7baebb573cdb31a20722a23dce204b/inc/lib/Biber.pm line 1940.
Use of uninitialized value $llabel in concatenation (.) or string at /tmp/par-adessec/cache-1810d1114b7baebb573cdb31a20722a23dce204b/inc/lib/Biber.pm line 1943.
Use of uninitialized value $llabel in concatenation (.) or string at /tmp/par-adessec/cache-1810d1114b7baebb573cdb31a20722a23dce204b/inc/lib/Biber.pm line 1944.
INFO - Writing 'test.bbl' with encoding 'UTF-8'
% $ biblatex auxiliary file $
% $ biblatex bbl format version 2.2 $
% Do not modify the above lines!
%
% This is an auxiliary file used by the 'biblatex' package.
% This file may safely be deleted. It will be recreated by
% biber as required.
%
\begingroup
\makeatletter
\@ifundefined{ver@biblatex.sty}
  {\@latex@error
     {Missing 'biblatex' package}
     {The bibliography requires the 'biblatex' package.}
      \aftergroup\endinput}
  {}
\endgroup
\refsection{0}
Use of uninitialized value in string comparison (cmp) at /tmp/par-adessec/cache-1810d1114b7baebb573cdb31a20722a23dce204b/inc/lib/Biber/Output/bbl.pm line 493.
Use of uninitialized value in string eq at /tmp/par-adessec/cache-1810d1114b7baebb573cdb31a20722a23dce204b/inc/lib/Biber/Output/bbl.pm line 494.
Use of uninitialized value in string eq at /tmp/par-adessec/cache-1810d1114b7baebb573cdb31a20722a23dce204b/inc/lib/Biber/Output/bbl.pm line 494.
Use of uninitialized value in string eq at /tmp/par-adessec/cache-1810d1114b7baebb573cdb31a20722a23dce204b/inc/lib/Biber/Output/bbl.pm line 494.
Use of uninitialized value in string eq at /tmp/par-adessec/cache-1810d1114b7baebb573cdb31a20722a23dce204b/inc/lib/Biber/Output/bbl.pm line 494.
Use of uninitialized value $label in string eq at /tmp/par-adessec/cache-1810d1114b7baebb573cdb31a20722a23dce204b/inc/lib/Biber/SortLists.pm line 77.
Use of uninitialized value $label in string eq at /tmp/par-adessec/cache-1810d1114b7baebb573cdb31a20722a23dce204b/inc/lib/Biber/SortLists.pm line 77.
Use of uninitialized value in string eq at /tmp/par-adessec/cache-1810d1114b7baebb573cdb31a20722a23dce204b/inc/lib/Biber/SortLists.pm line 77.
Use of uninitialized value $label in string eq at /tmp/par-adessec/cache-1810d1114b7baebb573cdb31a20722a23dce204b/inc/lib/Biber/SortLists.pm line 77.
  \sortlist{entry}{MAIN}
    \entry{test1}{book}{}
      \field{sortinit}{s}
    \endentry
  \endsortlist
Use of uninitialized value $listlabel in concatenation (.) or string at /tmp/par-adessec/cache-1810d1114b7baebb573cdb31a20722a23dce204b/inc/lib/Biber/Output/bbl.pm line 508.
Use of uninitialized value $listlabel in concatenation (.) or string at /tmp/par-adessec/cache-1810d1114b7baebb573cdb31a20722a23dce204b/inc/lib/Biber/Output/bbl.pm line 510.
  \sortlist{entry}{}
    \entry{test1}{book}{}
      \field{sortinit}{s}
    \endentry
  \endsortlist
\endrefsection
\endinput

INFO - Output to test.bbl
INFO - WARNINGS: 2

Removal of the temporary directory will not help. This will just regenerate as soon as biber is launched again. Any ideas?