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The CSLaTeX package is obsolete and it will be maintained no more.
This is our decision discussed on the CSTeX list 

  https://groups.google.com/forum/?fromgroups#!forum/cz.comp.cstex

in October 2012.

The last two changes was done by Petr Olsak in Oct.2012.

1) in cslatex.ini file: The cslatex.fmt is generated as usual but there
   is one difference. The \everyjob gives the following message:

   ***** WARNING ******** CSLaTeX is obsolete, don't use it please *****
   ***** You can use ``normal'' LaTeX+Babel or XeLaTeX+polyglossia *****

2) The files czech.sty and slovak.sty are obsolete too. But they was moved
   from csplain package to their right place: to the cslatex package.

3) The cslatex files from cspsfonts.tar.gz was moved to cslatex.tar.gz

That's all.