mention libidn

diff --git a/doc/cha-library.texi b/doc/cha-library.texi
index 92a5e05aa30caa3f32a72dfb7e4b14b5897541de..58c71b62475d3054e5554e1ed664a697e90011ce 100644 (file)
--- a/doc/cha-library.texi
+++ b/doc/cha-library.texi
@@ -80,11 +80,11 @@ want to install it separately (e.g., to make it possibly to use
 libtasn1 in other programs), you can get it from
 @url{http://www.gnu.org/software/libtasn1/}.
 
-The compression library, @code{libz}, the PKCS #11 helper library @code{p11-kit}, as well
-as the TPM library @code{trousers}, are 
-optional dependencies. You may get libz from @url{http://www.zlib.net/}, 
-p11-kit from @url{http://p11-glue.freedesktop.org/} and trousers from
-@url{http://trousers.sourceforge.net/}.
+The compression library, @code{libz}, the PKCS #11 helper library @code{p11-kit},
+the TPM library @code{trousers}, as well as the IDN library @{libidn}@footnote{Needed
+to use RFC6125 name comparison in internationalized domains.} are 
+optional dependencies. Check the README file in the distribution on how
+to obtain these libraries.
 
 A few @code{configure} options may be relevant, summarized below.
 They disable or enable particular features,