document python requirements

diff --git a/README b/README
index ff223098cf9a8dfa70202d2a8c2688c75e078cc6..d1df141c85dc851301fe3ae78dfebca3d22170cc 100644 (file)
--- a/README
+++ b/README
@@ -324,6 +324,9 @@ Building
        To support compression on the HTTP statistics channel, the
        server must be linked against libzlib (--with-zlib=/prefix).
 
+       Python requires 'argparse' and 'ply' to be available.
+       'argparse' is a standard module as of Python 2.7 and Python 3.2.
+
        On some platforms it is necessary to explicitly request large
        file support to handle files bigger than 2GB.  This can be
        done by "--enable-largefile" on the configure command line.