Spec docs for IDNA2008 support

(cherry picked from commit 91ef504cad49dd5c710f53816306a935b0ecc29e)
Signed-off-by: Phil Pennock <pdp@exim.org>

diff --git a/doc/doc-docbook/spec.xfpt b/doc/doc-docbook/spec.xfpt
index da2a41a2e4114b48bb64c6a89705334efe49089d..5cbc126a488a43557b13037421a99c37137ff7ed 100644 (file)
--- a/doc/doc-docbook/spec.xfpt
+++ b/doc/doc-docbook/spec.xfpt
@@ -38747,6 +38747,12 @@ Exim has support for Internationalised mail names.
 To include this it must be built with SUPPORT_I18N and the libidn library.
 Standards supported are RFCs 2060, 5890, 6530 and 6533.
 
+.new
+If Exim is built with SUPPORT_I18N_2008 (in addition to SUPPORT_I18N, not
+instead of it) then IDNA2008 is supported; this adds an extra library
+requirement, upon libidn2.
+.wen
+
 .section "MTA operations" SECTi18nMTA
 .cindex SMTPUTF8 "ESMTP option"
 The main configuration option &%smtputf8_advertise_hosts%& specifies