[pstricks] babel clashing with the arrow arguments

[Ales Horak]

Hi all,

I had encountered a problem with the arrow arguments for PSTricks
node connections. to reproduce it (I am using texlive-2009-7 on
ubuntu) I have done:

    - download pstricks and pst-node of June 14 2011 to pstricks
      subdirectory
    - create node.tex:

        \documentclass{article}
        \usepackage[czech]{babel}
        \usepackage{pst-node}

        \begin{document}

        \cnode(0,1){.25}{A}
        \pnode(3,0){B}
        \ncline{<-}{A}{B}

        \end{document}

    - run:

        TEXINPUTS=:pstricks/generic:pstricks/latex latex node.tex
        DVIPSHEADERS=:pstricks/dvips dvips -o node.ps node.dvi
        ps2pdf node.ps

      the last one ends with:

        Error: /syntaxerror in -file-
        Operand stack:
           0.0   -0.0   0.0   0.0   0   0   N@
        Execution stack:
           %interp_exit   .runexec2   --nostringval--   --nostringval--   --nostringval--   2   %stopped_push   --nostringval--   --nostringval--   --nostringval--   false   1   %stopped_push   1878   1   3   %oparray_pop   1877   1   3   %oparray_pop   1861   1   3   %oparray_pop   1755   1   3   %oparray_pop   --nostringval--   %errorexec_pop   .runexec2   --nostringval--   --nostringval--   --nostringval--   2   %stopped_push
        Dictionary stack:
           --dict:1157/1684(ro)(G)--   --dict:0/20(G)--   --dict:81/200(L)--   --dict:175/300(L)--   --dict:112/200(L)--   --dict:51/400(L)--
        Current allocation mode is local
        Last OS error: 2
        Current file position is 111721
        GPL Ghostscript 8.71: Unrecoverable error, exit code 1

This error disappears if I

    1. remove \usepackage[czech]{babel}
       this is, however, unwanted

    2. change \ncline line to

        \ncline[arrows=<-]{A}{B}

       this works great and (probably) without any other
       problems. It just does not correspond to the examples in
       the documentation.

I suppose that this is some babel-related problem, but I do not
know, whether it is easily correctable. I am posting it here
since I have not found this workaround anywehere before.       

best regards,
-- 
Ales Horak